North Korea’s Nuclear Weapons:
Technical Issues
Mary Beth Nikitin
Analyst in Nonproliferation
January 8, 2010
Congressional Research Service
7-5700
www.crs.gov
RL34256
CRS Report for Congress
P
repared for Members and Committees of Congress
North Korea’s Nuclear Weapons: Technical Issues
Summary
This report summarizes what is known from open sources about the North Korean nuclear
weapons program—including weapons-usable fissile material and warhead estimates—and
assesses current developments in achieving denuclearization.
In total, it is estimated that North Korea has between 30 and 50 kilograms of separated plutonium,
enough for at least half a dozen nuclear weapons. While North Korea’s weapons program has
been plutonium-based from the start, in the last decade, intelligence emerged pointing to a second
route to a bomb using highly enriched uranium. However, the scope and success of a uranium
enrichment program may be limited. Little detailed open-source information is available about
the DPRK’s nuclear weapons production capabilities, warhead sophistication, the extent of a
uranium enrichment program, or proliferation activities.
Beginning in late 2002, North Korea ended an eight-year freeze on its plutonium production
program, expelled international inspectors, and restarted facilities. In September 2005, members
of the Six Party Talks (United States, South Korea, Japan, China, Russia, and North Korea) issued
a Joint Statement on the verifiable denuclearization of the Korean Peninsula. On October 9, 2006,
North Korea conducted a nuclear test, with a yield of less than 1 kiloton. In February 2007, North
Korea and the other members of the Six-Party Talks agreed on steps for phased implementation of
the 2005 denuclearization agreement. Phase 1 included the shut-down of plutonium production at
the Yongbyon nuclear complex in exchange for an initial heavy fuel oil shipment to North Korea.
Phase 2 steps included disablement of plutonium production facilities at Yongbyon and a
“complete and correct” declaration of DPRK nuclear activities, in exchange for delivery of
energy assistance and removal of certain U.S. sanctions. The declaration was submitted in June
2008. Thereafter, President Bush removed North Korea from the Trading with the Enemy Act
(TWEA) list and notified Congress of his intent to lift the State Sponsor of Terrorism (SST)
designation after North Korea agreed to verification provisions. North Korea did not accept initial
U.S. verification proposals, and in September 2008, threatened to restart reprocessing plutonium.
U.S. officials announced a verbal bilateral agreement on verification in October 2008, and the
Bush administration removed North Korea from the SST List. North Korea soon after said that it
had not agreed to sampling at nuclear sites, a key element for verification of plutonium
production. The Six-Party Talks have not convened since December 2008.
North Korea’s failed satellite launch on April 5, 2009, which used ballistic missile-related
technology, led to U.N. Security Council condemnation. In response, North Korea said it would
abandon the Six-Party Talks and restart its nuclear facilities, and asked international and U.S.
inspectors to leave the country. North Korea claimed it tested a nuclear weapon on May 25, 2009,
which is estimated as larger than the 2006 blast, but still modest. Through its official news
agency, North Korea claimed in September 2009 that it was conducting “experimental uranium
enrichment” and in November 2009 that it had reprocessed spent fuel at the Yongbyon facility
and had begun to weaponize the resulting plutonium.
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North Korea’s Nuclear Weapons: Technical Issues
Contents
Latest Developments................................................................................................................... 1
Background ................................................................................................................................ 1
Weapons Production Milestones.................................................................................................. 3
Estimating Nuclear Warheads and Plutonium Stocks ............................................................. 4
Plutonium Production ........................................................................................................... 5
A Uranium Enrichment Program? ......................................................................................... 7
The October 9, 2006, Nuclear Test ...................................................................................... 10
The May 25, 2009, Test....................................................................................................... 10
Delivery Systems ................................................................................................................ 11
Doctrine and Intent ............................................................................................................. 12
Steps Toward Denuclearization Under the Six Party Talks ......................................................... 12
Disablement ........................................................................................................................ 13
Reversing Disablement ....................................................................................................... 15
Declaration ......................................................................................................................... 16
Verification ......................................................................................................................... 17
Future Considerations ......................................................................................................... 20
Proliferation Issues.................................................................................................................... 21
Issues for Congress ................................................................................................................... 22
Funding .............................................................................................................................. 22
Authority ............................................................................................................................ 23
Policy Guidance.................................................................................................................. 24
Tables
Table 1. Disablement Steps at Yongbyon, DPRK ....................................................................... 13
Contacts
Author Contact Information ...................................................................................................... 24
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Latest Developments
North Korea’s failed satellite launch on April 5, 2009, which used ballistic missile-related
technology, led to U.N. Security Council condemnation. In response, North Korea said it would
abandon the Six-Party Talks and restart its nuclear facilities, and asked international and U.S.
inspectors to leave the country immediately. The DPRK informed the IAEA that it has “decided
to reactivate all facilities and go ahead with the reprocessing of spent fuel.” 1 North Korean
officials have also threatened to conduct another nuclear test, build a light-water reactor, and
“start the technological development for ensuring self-production of nuclear fuel,” which may be
a reference to a uranium enrichment program.2
North Korea conducted its second nuclear test on May 25, 2009. The Office of the Director of
National Intelligence estimated the yield of the test to be a few kilotons. In response, the United
Nations Security Council (UNSC) unanimously passed Resolution 1874 on June 12, condemning
the test and applying new sanctions to block arms, WMD, and missile-related financing and
shipments. In response to the UNSC resolution, Pyongyang issued a statement saying North
Korea would weaponize the plutonium in its spent fuel, “commence” the uranium enrichment
“process,” and that any blockade would be considered an act of war. This was the first time the
DPRK had acknowledged a uranium enrichment program in a public statement.
In a September 2009 letter to the president of the UN Security Council, Pyongyang’s permanent
representative to the UN announced countermeasures to UN Security Council sanctions. The
letter said that “reprocessing of spent fuel rods is at its final phase and extracted plutonium is
being weaponized,” and “experimental uranium enrichment has successfully been conducted to
enter the completion phase.” In early November 2009, the North Korean news agency announced
that all 8,000 spent fuel rods in its possession had been reprocessed by the end of August. The
statement said that the resulting plutonium was being weaponized. There is no indication to date
that North Korea is reconstituting its nuclear power reactor at Yongbyon.
Background
In the early 1980s, U.S. satellites tracked a growing indigenous nuclear program in North Korea.
The North Korean nuclear program began in the late 1950s with cooperation agreements with the
Soviet Union on a nuclear research program near Yongbyon. Its first research reactor began
operation in 1967. North Korea used indigenous expertise and foreign procurements to build a
small nuclear reactor at Yongbyon (5MWe). It was capable of producing about 6 kilograms (Kg)
of plutonium per year and began operating in 1986.3 Later that year, U.S. satellites detected high
explosives testing and a new plant to separate plutonium from the reactor’s spent fuel. In
addition, construction of two larger reactors (50MWe at Yongbyon and 200MWe at Taechon)
added evidence of a serious clandestine effort. Although North Korea had joined the Nuclear
Nonproliferation Treaty (NPT) in 1985 under Soviet pressure, safeguards inspections began only
1 “IAEA Inspectors Asked to Leave the Democratic People’s Republic of Korea,” IAEA Press Release, April 14, 1009,
http://www.iaea.org/NewsCenter/PressReleases/2009/prn200903.html.
2 Choe Sang-Hun, “North Korea Issues Threat on Uranium,” The New York Times, April 29, 2009.
3 5MWe is a power rating for the reactor, indicating that it produces 5 million watts of electricity per day (very small).
Reactors are also described in terms of million watts of heat (MW thermal).
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in 1992, raising questions about how much plutonium North Korea had produced covertly. In
1994, North Korea pledged, under the Agreed Framework with the United States, to freeze its
plutonium programs and eventually dismantle them in return for several kinds of assistance.4 At
that time, western intelligence agencies estimated that North Korea had separated enough
plutonium for one or two bombs. North Korea complied with the Agreed Framework, allowing
International Atomic Energy Agency (IAEA) seals—including the “canning” of spent fuel rods at
the Yongbyon reactor—and permanent remote monitoring and inspectors at its nuclear facilities.
When in 2002, U.S. negotiators reportedly presented North Korean officials with evidence of a
clandestine uranium enrichment program, the North Korean officials reportedly at first confirmed
this, then denied it publicly. The conflict quickly led to the breakdown of the Agreed Framework.
The Bush Administration argued that North Korea was in “material breach” of its obligations and,
after agreement with South Korea, Japan, and the EU (the other members of the Korean
Economic Development Organization, or KEDO), stopped the next shipment of heavy fuel oil.5
In response, North Korea kicked out international monitors, broke the seals at the Yongbyon
nuclear complex, and restarted its reactor and reprocessing plant after an eight-year freeze.
Members of the Six-Party Talks—the United States, South Korea, Japan, China, Russia, and
North Korea—began meeting in August 2003 to try and resolve the crisis. In September 2005, the
Six Parties issued a Joint Statement on how to achieve verifiable denuclearization of the Korean
Peninsula, which formed the basis for future agreements.6 Negotiations broke down, and North
Korea tested a nuclear device in October 2006.
On February 13, 2007, North Korea reached an agreement with other members of the Six-Party
Talks to begin the initial phase (60 days) of implementing the Joint Statement from September
2005 on denuclearization. Phase 1 of this agreement included the shut-down of plutonium
production at the Yongbyon nuclear complex in exchange for an initial heavy fuel oil shipment to
North Korea. Phase 2 steps include the disablement of facilities at Yongbyon and a “complete and
correct” declaration of DPRK nuclear activities, in exchange for deliver of heavy fuel oil and
equivalent, and removal of the Trading with the Enemy Act (TWEA) and State Sponsors of
Terrorism (SST) designations. Still in the second phase of this plan, the United States is working
with North Korea to disable key facilities. The U.S. provides funding and technical assistance for
disablement activities, and the energy assistance is divided evenly between the Six Parties. North
Korea submitted a declaration of its past plutonium production activities in June 2008 as agreed
in an October 3, 2007, joint statement on “Second-Phase Actions.”7 Thereafter, President Bush
removed North Korea from the TWEA list and notified Congress of his intent to lift the SST
designation after North Korea agreed to verification provisions. North Korea did not accept initial
U.S. verification proposals, and in September 2008, threatened to restart reprocessing plutonium.
U.S. officials announced a bilateral agreement on verification in October 2008, and the Bush
administration removed North Korea from the SST List. The agreement was verbal, and North
Korea then said that it had not agreed to sampling at nuclear sites, a key element in verifying past
4 See CRS Report RL33590, North Korea’s Nuclear Weapons Development and Diplomacy, by Larry A. Niksch and
CRS Report R40095, Foreign Assistance to North Korea, by Mark E. Manyin and Mary Beth Nikitin.
5 “Adherence To and Compliance With Arms Control, Nonproliferation and Disarmament Agreements and
Commitments,” U.S. Department of State, August 2005.
6 “Joint Statement of the Fourth Round of the Six-Party Talks, Beijing,” September 19, 2005, at http://www.state.gov/r/
pa/prs/ps/2005/53490.htm.
7 Second-Phase Actions for the Implementation of the September 2005 Joint Statement, October 3, 2007
http://www.state.gov/r/pa/prs/ps/2007/oct/93223.htm.
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plutonium production. The Six Parties met in December 2008, but did not reach agreement on
verification measures. Disablement activities at Yongbyon continued through April 2009, when
North Korea expelled international monitors. North Korea then announced it would restart its
reprocessing plant and boasted progress in uranium enrichment technology development (see
detailed discussion below).
The February 2007 Denuclearization Action Plan did not address any uranium enrichment-related
activities or the dismantlement of warheads and instead focused on shutting down and disabling
the key plutonium production facilities at Yongbyon. A third phase, to have begun after
disablement was complete and a declaration accepted by the Six Parties, was expected to deal
with all aspects of North Korea’s nuclear program, including weapons, using North Korea’s
declaration as a basis for future action. Understanding the scope of the program and the weapons
capability would require transparency and careful verification for the pledged “complete,
verifiable, irreversible” disarmament to be achieved.
Weapons Production Milestones
Acquiring fissile material—plutonium-239 or highly enriched uranium (HEU)—is the key hurdle
in nuclear weapons development.8 Producing these two materials is technically challenging; in
comparison, many experts believe weaponization to be relatively easy.9 North Korea has
industrial-scale uranium mining and plants for milling, refining, and converting uranium; it also
has a fuel fabrication plant, a nuclear reactor, and a reprocessing plant—in short, everything
needed to produce Pu-239. In its nuclear reactor, North Korea uses magnox fuel—natural
uranium (>99%U-238) metal, wrapped in magnesium-alloy cladding. About 8,000 fuel rods
constitute a fuel core for the reactor.
When irradiated in a reactor, natural uranium fuel absorbs a neutron and then decays into
plutonium (Pu-239). Fuel that remains in the reactor for a long time becomes contaminated by the
isotope Pu-240, which can “poison” the functioning of a nuclear weapon.10 Spent or irradiated
fuel, which poses radiological hazards, must cool after removal from the reactor. The cooling
phase, estimated by some at five months, is proportional to the fuel burn-up. Reprocessing to
separate plutonium from waste products and uranium is the next step. North Korea uses a PUREX
separation process, like the United States. After shearing off the fuel cladding, the fuel is
dissolved in nitric acid. Components (plutonium, uranium, waste) of the fuel are separated into
different streams using organic solvents. In small quantities, separation can be done in hot cells,
but larger quantities require significant shielding to prevent deadly exposure to radiation.11
8 Highly enriched uranium (HEU) has 20% or more U-235 isotope; 90% U-235 is weapons-grade.
9 The physical principles of weaponization are well-known, but producing a weapon with high reliability, effectiveness,
and efficiency without testing presents significant challenges.
10 Plutonium that stays in a reactor for a long time (reactor-grade, with high “burn-up”) contains about 20% Pu-240;
weapons-grade plutonium contains less than 7% Pu-240.
11 Hot cells are heavily shielded rooms with remote handling equipment for working with irradiated materials. For
background, see Jared S. Dreicer, “How Much Plutonium Could Have Been Produced in the DPRK IRT
Reactor?”Science and Global Security, 2000, vol. 8, pp. 273-286, at http://www.princeton.edu/sgs/publications/sgs/pdf/
8_3Dreicer.pdf.
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North Korea appears to have mastered the engineering requirements of plutonium production. It
has operated its nuclear reactor, is believed to have separated Pu from the spent fuel, and has
reportedly taken steps toward weaponization. In January 2004, North Korean officials showed an
unofficial U.S. delegation alloyed “scrap” from a plutonium (Pu) casting operation.12 Dr.
Siegfried Hecker, a delegation member, assessed that the stated density of the material was
consistent with plutonium alloyed with gallium or aluminum. If so, this could indicate a degree of
sophistication in North Korea’s handling of Pu metal, necessary for weapons production. But
without testing the material, Hecker could not confirm that the metal was plutonium or that it was
alloyed, or when it was produced.
Estimating Nuclear Warheads and Plutonium Stocks
Secretary of State Colin Powell in December 2002 stated, “We now believe [the North Koreans]
have a couple of nuclear weapons and have had them for years.”13 In February 2005, North Korea
officially announced that it had “manufactured nukes for self-defense.”14 Vice Foreign Minister
Kim Gye Gwan has previously said that North Korea possesses multiple bombs and was building
more.15
A key factor in assessing how many weapons North Korea can produce is whether North Korea
needs to use more or less material than the IAEA standards of 8kg of Pu and 25kg for HEU per
weapon.16 The amount of fissile material used in each weapon is determined by the design
sophistication. There is no reliable public information on North Korean nuclear weapons design.
In all, estimates of North Korea’s separated plutonium range between 30 and 50 kg, with an
approximate 5 to 6 kg of this figure having been used for the October 2006 test and an additional
amount probably used in the May 2009 test. 17 This amounts to enough plutonium for
approximately five to eight nuclear weapons, assuming 6 kg per weapon. Taking the nuclear tests
into account, North Korean could possess plutonium for four to seven nuclear weapons. A 2007
unclassified intelligence report to Congress says that “prior to the test North Korea could have
produced up to 50 kg of plutonium, enough for at least a half dozen nuclear weapons” and points
out that additional plutonium is in the fuel of the Yongbyon reactor.18 North Korea claimed to
have reprocessed that fuel in the summer of 2009 (see below).
12 Alloying plutonium with other materials is “common in plutonium metallurgy to retain the delta-phase of plutonium,
which makes it easier to cast and shape” (two steps in weapons production). Hecker, January 21, 2004, testimony
before SFRC.
13 Transcript of December 29, 2002, Meet the Press.
14 James Brooke, “North Korea says it has atom arms It will boycott talks on ending program; arsenal called self-
defense against Bush,” The New York Times, February 11, 2005.
15 “We have enough nuclear bombs to defend against a U.S. attack. As for specifically how many we have, that is a
secret.” “North Korea Admits Building More Nuclear Bombs,” ABC News, June 8, 2005, at http://abcnews.go.com/
WNT/story?id=831078&page=1.
16 IAEA Safeguards Glossary: http://www-pub.iaea.org/MTCD/publications/PDF/nvs-3-cd/PDF/NVS3_scr.pdf.
17 Siegfried Hecker estimates 40-50 kg of separated plutonium and 6 kg for the 2006 test; David Albright and Paul
Brannan’s study says 33-55 kg of separated plutonium and roughly 5 kg for the 2006 test. U.S. Assistant Secretary of
State Christopher Hill cites 50 kg in his comments. Hecker, ibid. David Albright and Paul Brannan, “The North Korean
Plutonium Stock February 2007,” Institute for Science and International Security, February 20, 2007. Christopher Hill,
“Interview on PBS NewsHour,” October 3, 2007, at http://www.state.gov/p/eap/rls/rm/2007/93274.htm.
18 Unclassified Report to Congress on Nuclear and Missile Programs of North Korea, Office of the Director of National
Intelligence, August 8, 2007.
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Questions arise in determining how much plutonium North Korea produced between 2003, when
the IAEA monitors were kicked out of the country and the seals were broken at Yongbyon, and
2007, when international monitoring resumed. A South Korean Defense Ministry white paper
from December 2006 estimated that North Korea had made 30 kg of weapons-grade plutonium in
the previous three years, potentially enough for five nuclear bombs. The white paper also
concurred with U.S. estimates that North Korea’s total stockpile of weapons-grade plutonium was
50 kg.19
The accounting issue was further complicated when North Korea reportedly declared a lower
number of 37 kg of separated plutonium in its declaration under the Six Party Talks.20 No
agreement has been reached on verifying the amount of plutonium stocks through inspections
(see discussions on declaration, verification below). In January 2009, an American scholar who
had visited Pyongyang said the North Koreans told him that 30.8 kg amount had been
“weaponized,” possibly meaning that the separated plutonium might now be in warheads. The
DPRK officials also told him that they would not allow for warheads to be inspected.21
Plutonium Production
Estimates of plutonium production depend on a variety of technical factors, including the average
power level of the reactor, days of operation, how much of the fuel is reprocessed and how
quickly, and how much plutonium is lost in production processes. North Korean officials claimed
to have separated plutonium in hot cells as early as 1975 and tested the reprocessing plant in
1990. North Korea’s 5MWe nuclear reactor at Yongbyon operated from 1986 to 1994. It is
estimated that North Korea produced and separated no more than 10 kg of plutonium prior to
1994.22 Its plutonium production program was then frozen between 1994 and 2003 under the
Agreed Framework. When this agreement was abandoned, North Korea restarted plutonium
production at Yongbyon.
On February 6, 2003, North Korean officials announced that the 5MWe reactor was operating,
and commercial satellite photography confirmed activity in March. In January 2004, North
Korean officials told an unofficial U.S. delegation that the reactor was operating smoothly at
100% of its rated power. The U.S. visitors noted that the display in the reactor control room and
steam plumes from the cooling towers confirmed operation, but that there was no way of knowing
how it had operated over the last year.23
The same delegation reported that the reprocessing “facility appeared in good repair,” in contrast
to a 1992 IAEA assessment of the reprocessing plant as “extremely primitive.” According to
North Korean officials in January 2004, the reprocessing plant’s annual throughput is 110 tons of
spent fuel, about twice the fuel load of the 5MWe reactor. Officials claimed to have reprocessed
all 8,000 fuel rods from the 5MWe reactor between January and June 2003.24 Reprocessing the
19 “North Korea ‘serious threat’ to South,” BBC News, http://news.bbc.co.uk/2/hi/asia-pacific/6216385.stm.
20 Warren Strobel, “North Korean nuclear documents challenge CIA assertions,” McClatchyNewspapers, May 28,
2008.
21 “N.K. says plutonium ‘weaponized’ and off-limits,” The Korea Herald, January 19, 2009.
22 David Albright and Paul Brannan, “The North Korean Plutonium Stock February 2007.”
23 Siegfried Hecker, January 21, 2004, testimony before Senate Foreign Relations Committee.
24 “North Korea Says It Has Made Fuel For Atom Bombs,” New York Times, July 15, 2003.
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8,000 fuel rods at that time would have yielded between 25 and 30kg of plutonium, perhaps for
four to six weapons, but the exact amount of plutonium that might have been reprocessed is
unknown. In 2004, North Korean officials stated that the reprocessing campaign was conducted
continuously (in four six-hour shifts).
In April 2005, the 5MWe reactor was shut down, this time to harvest fuel rods for weapons.25 The
reactor resumed operations in June 2005.26 One estimate is that the reactor held between 10 and
15 kg of Pu in April 2005, and that North Korea could have reprocessed all the fuel rods by mid-
2006. From August 2005 to 2006, the reactor could have produced another 6 kg of Pu. In total,
North Korea could have reprocessed enough separated plutonium for another three weapons (in
addition to the estimated 4-6 bomb-worth from reprocessing the 8,000 fuel rods).27 The 5MWe
reactor was again shut down in July 2007, when the IAEA installed containment and surveillance
measures and radiation monitoring devices.28 Its cooling tower was destroyed in June 2008. The
IAEA was asked to remove its monitoring equipment and leave the site in April 2009. In early
November 2009, the North Korean news agency announced that all 8,000 spent fuel rods in its
possession had been reprocessed by the end of August. Reprocessing at that time, is estimated to
have produced 7-8 kg of separated plutonium or approximately enough for one nuclear
warhead.29
No construction has occurred at the 50MWe reactor at Yongbyon or at the 200MWe Taechon
reactor since 2002.30 They were years from completion when construction was halted. U.S.
visitors in January 2004 saw heavy corrosion and cracks in concrete building structures at
Yongbyon, reporting that the reactor building “looks in a terrible state of repair.”31 The CIA
estimated that the two reactors could generate about 275kg of plutonium per year if they were
operating.32 Dr. Hecker estimated that if the 50MWe reactor was functioning, it would mean a
tenfold increase in North Korea’s plutonium production.33 North Korea agreed to halt work on
reactors as part of the Six Party Talks. From July 2007 to April 2009, when inspectors were asked
to leave, the IAEA was monitoring to ensure that no further construction took place at these sites.
Significant future growth in North Korea’s arsenal would be possible only if the two larger
reactors were completed and operating, and would depend on progress in the reported uranium
enrichment program. However, even when the reprocessing facility was shut down, North Korea
25 “North Koreans Claim to Extract Fuel for Nuclear Weapons,” New York Times, May 12, 2005.
26 David Albright and Paul Brannan, “The North Korean Plutonium Stock February 2007,” Institute for Science and
International Security, February 20, 2007.
27 Technical difficulties associated with the fuel fabrication facility may have slowed how often the fuel was unloaded
from the reactor, limiting production to at most one bomb per year. Siegfried Hecker, “Report on North Korean
Nuclear Program,” Center for International Security and Cooperation, Stanford University, November 15, 2006.
28 IAEA Team Confirms Shut Down of DPRK Nuclear Facilities, http://www.iaea.org/NewsCenter/PressReleases/
2007/prn200712.html.
29 Siegfried Hecker, “The Risks of North Korea’s Nuclear Restart,” Bulletin of the Atomic Scientists, May 12, 2009,
http://www.thebulletin.org/web-edition/features/the-risks-of-north-koreas-nuclear-restart
30 Report by the Director General to the IAEA Board of Governors, “Applications of Safeguards in the Democratic
People’s Republic of Korea (DPRK),” GOV/2007/45-GC(51)/19, August 17, 2007.
31 Hecker January 21, 2004, testimony before SRFC.
32 CIA unclassified point paper distributed to congressional staff on November 19, 2002.
33 Siegfried Hecker, “Report on North Korean Nuclear Program,” Center for International Security and Cooperation,
Stanford University, November 15, 2006.
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could have built additional warheads with existing separated plutonium because North Korea’s
plutonium stocks were not under IAEA safeguards.
A Uranium Enrichment Program?
While North Korea’s weapons program has been plutonium-based from the start, in the last
decade, intelligence has emerged pointing to a second route to a bomb using highly enriched
uranium. There is some certainty that North Korea has parts and plans for such a program, and
less certainty over how far this program has developed. The issue has been central to negotiations
since October 2002, when the Bush Administration accused North Korea of having a clandestine
uranium enrichment program. U.S. lead negotiator James Kelly told North Korean First Deputy
Foreign Minister Kang Sok-chu that the United States had evidence of a uranium enrichment
program for nuclear weapons in violation of the Agreed Framework and other agreements. James
Kelly said that Kang acknowledged the existence of such a program at that meeting. However,
Kang later denied this, and Foreign Minister Paek Nam Sun said that Kang had told Kelly that
North Korea is “entitled” to have such a program or “an even more powerful one” to deter a pre-
emptive U.S. attack.34
A 2002 unclassified CIA working paper on North Korea’s nuclear weapons and uranium
enrichment estimated that North Korea “is constructing a plant that could produce enough
weapons-grade uranium for two or more nuclear weapons per year when fully operational—
which could be as soon as mid-decade.” Such a plant would need to produce more than 50kg of
HEU per year, requiring cascades of thousands of centrifuges.35 The paper noted that in 2001,
North Korea “began seeking centrifuge-related materials in large quantities.” Pakistani President
Musharraf revealed in his September 2006 memoir, In the Line of Fire, that Abdul Qadeer
Khan—chief scientist in Pakistan’s nuclear weapons program who proliferated nuclear weapons
technology for profit—”transferred nearly two dozen P-1 and P-2 centrifuges to North Korea. He
also provided North Korea with a flow meter, some special oils for centrifuges, and coaching on
centrifuge technology, including visits to top-secret centrifuge plants.”36 However, the United
States has not been able to get direct confirmation from Khan. According to press reports, North
Korea said it had imported 150 tons of high-strength aluminum tubes from Russia that could be
used in a uranium enrichment program.37
Questions have been raised about whether the 2002 estimates were accurate.38 In a hearing before
the Senate Armed Services Committee on February 27, 2007, Joseph DeTrani, the mission
manager for North Korea from the Office of the Director of National Intelligence and former
34 Selig Harrison, “Did North Korea Cheat?” Foreign Affairs, vol. 84, no. 1, January/February 2005.
35 North Korea would first have to convert uranium “yellowcake” into uranium hexafluoride to feed into the
centrifuges. The centrifuges would “enrich” the uranium, or increase the portion of U-235. Weapons-grade enriched
uranium according to the IAEA needs to have an enrichment level of at least 20%. See CRS Report RL34234,
Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power, coordinated by
Mary Beth Nikitin.
36 Pervez Musharraf, In the Line of Fire: A Memoir, (New York: Free Press, September 2006), p. 296.
37 “NK Admits to Buying Aluminum Tubes,” KBS World News, September 27, 2007, and Takashi Sakamoto, “DPRK
Admits To Importing Aluminum Tubes From Russia for Uranium Enrichment,” Yomiuri Shimbun, in Japanese,
Translated by BBC Monitoring Asia Pacific, October 26, 2007.
38 Paul Kerr, “News Analysis: Doubts Rise on North Korea’s Uranium-Enrichment Program,” Arms Control Today,
April 2007, at http://www.armscontrol.org/act/2007_04/NewsAnalysis.asp.
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chief negotiator for the Six Party Talks, was asked by Senator Jack Reed whether he had “any
further indication of whether that program has progressed in the last six years, one; or two, the
evidence—the credibility of the evidence that we had initially, suggesting they had a program
rather than aspirations?” DeTrani responded that “the assessment was with high confidence that,
indeed, they were making acquisitions necessary for, if you will, a production-scale program. And
we still have confidence that the program is in existence—at the mid-confidence level.” In a
clarification of his response, DeTrani issued a DNI press release that said there was a high level
of confidence in 2002 that North Korea had a uranium enrichment program, and “at least
moderate confidence that North Korea’s past efforts to acquire a uranium enrichment capability
continue today.”39 Assistant Secretary of State Christopher Hill said in February 2007 that the
United States is not sure if North Korea has mastered “some considerable production techniques,”
although they have acquired some technology for an enrichment program.40
A DNI unclassified report of August 2007 stated,
We continue to assess with high confidence that North Korea has pursued efforts to acquire a
uranium enrichment capability, which we assess is intended for nuclear weapons. All
Intelligence Community agencies judge with at least moderate confidence that this past effort
continues. The degree of progress towards producing enriched uranium remains unknown,
however.41
In testimony to Congress on February 2008, Director of National Intelligence Michael McConnell
confirmed this assessment. The confidence level of these assessments may have changed because
of a decrease in international procurement by North Korea. Uranium enrichment-related imports
would be more easily detected by intelligence agencies than activities inside North Korea itself.
Uranium enrichment facilities can be hidden from aerial surveillance more easily than plutonium
facilities, making it more difficult for intelligence agencies to even detect—thus, “degree of
progress” in turning the equipment into a working enrichment program is “unknown.”
Furthermore, there are significant differences between assembling a small-scale centrifuge
enrichment program and operating a large-scale production plant, and reportedly little evidence of
procurement for a large-scale plant has emerged.42 Dr. Siegfried Hecker has assessed that it is
“highly likely that North Korea had a research and development uranium enrichment effort, but
there is little indication that they were able to bring it to industrial scale.”43
39 “There has been considerable misinterpretation of the Intelligence Community’s view of North Korean efforts to
pursue a uranium enrichment capability. The intelligence in 2002 was high quality information that made possible a
high confidence judgment about North Korea’s efforts to acquire a uranium enrichment capability. The Intelligence
Community had then, and continues to have, high confidence in its assessment that North Korea has pursued that
capability. We have continued to assess efforts by North Korea since 2002. All Intelligence Community agencies have
at least moderate confidence that North Korea’s past efforts to acquire a uranium enrichment capability continue
today.” ODNI News Release 04-07, March 4, 2007, at http://www.dni.gov/press_releases/20070304_release.pdf.
40 “Update on the Six Party Talks,” Brookings Institution, February 22, 2007, at http://www.brookings.edu/events/
2007/0222south-korea.aspx.
41 Unclassified Report to Congress on Nuclear and Missile Programs of North Korea, Office of the Director of National
Intelligence, August 8, 2007.
42 See David Albright, “North Korea’s Alleged Large-Scale Enrichment Plant: Yet Another Questionable Extrapolation
Based on Aluminum Tubes,” The Institute for Science and Security, February 23, 2007, at http://www.isis-online.org/
publications/dprk/DPRKenrichment22Feb.pdf.
43 Siegfried Hecker, “Denuclearizing North Korea,” Bulletin of the Atomic Scientists, May/June 2008.
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Until May 2009, North Korea denied the existence of a highly enriched uranium program for
weapons. In 2007, North Korea gave the United States a sample of the aluminum tubing in an
effort to prove that it never intended to produce highly enriched uranium for weapons, and that
the imported materials were for conventional weapons or dual-use projects. However, when U.S.
scientists analyzed the aluminum tubing provided as sample “evidence,” they found traces of
enriched uranium on the tubing. Analysts argue that in addition to the possibility that this is proof
of a North Korean uranium enrichment program, it is also possible that the uranium traces could
have been on the tubing when North Korea received it.44
In 2008, U.S. personnel found traces of highly-enriched uranium on the documents submitted as
part of North Korea’s nuclear declaration, raising new doubts about the extent of North Korea’s
uranium enrichment program.45 Ambassador Hill told Congress that North Korea included as part
of its June 2008 “declaration package” a letter that says that “they do not now and will not in the
future have a highly enriched uranium program.”46
The Section 721 Unclassified Report to Congress covering the period January 1 to December 31,
2008, said that
Although North Korea has halted and disabled portions of its plutonium production program,
we continue to assess North Korea has pursued a uranium enrichment capability at least in
the past. Some in the IC have increasing concerns that North Korea has an ongoing covert
uranium enrichment program.
In the spring of 2009, North Korea itself announced a uranium enrichment program. Following
the June 12 UN Security Council Resolution condemning North Korea’s nuclear test, Pyongyang
issued a statement: “The process of uranium enrichment will be commenced.” The statement also
said that “pursuant to the decision to build its own light-water reactor, enough success has been
made in developing uranium enrichment technology to provide nuclear fuel to allow the
experimental procedure.”47 North Korea had threatened in April that it would build a light-water
reactor if the UN Security Council did not apologize for its condemnation of the North’s missile
test. In the June statement, North Korea was apparently saying it would, at a minimum, start the
experimental enrichment of uranium for fuel.48 Pyongyang offered a further statement in
September 2009: “experimental uranium enrichment has successfully been conducted to enter the
completion phase.” However, it is unclear the extent to which it has carried out experimental
uranium enrichment, or what a “completion phase” means in technical terms. U.S. Special
Representative for North Korea Policy Ambassador Stephen Bosworth said after a bilateral
meeting in North Korea that the subject of a uranium enrichment program will be “on the agenda”
when the Six Party Talks resume.49
44 Glenn Kessler, “Uranium Traces Found on N. Korean Aluminum Tubes,” Washington Post, December 21, 2007, at
http://www.washingtonpost.com/wp-dyn/content/article/2007/12/20/AR2007122002196_pf.html.
45 Glenn Kessler, “New Data Found On North Korea’s Nuclear Capacity; Intelligence on Enriched Uranium Revives
Questions About Weapons,” The Washington Post, June 21, 2008.
46 Senate Armed Services Hearing on the North Korean Six-Party Talks and Implementation Activities, July 31, 2008.
47 http://www.kcna.co.jp/item/2009/200906/news13/20090613-10ee.html.
48 Hui Zhang, “Assessing North Korea’s Uranium Enrichment Capabilities,” Bulletin of the Atomic Scientists, June 28,
2009.
49 Department of State, “Briefing on Recent Travel to North Korea,” December 16, 2009, http://www.state.gov/p/eap/
rls/rm/2009/12/133718.htm
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The October 9, 2006, Nuclear Test50
The U.S. Director of National Intelligence confirmed that North Korea conducted an underground
nuclear explosion on October 9, 2006, in the vicinity of P’unggye.51 However, the sub-kiloton
yield of the test suggests that the weapon design or manufacturing process likely needs
improvement.52 North Korea reportedly told China before the test that it expected a yield of 4
kilotons (KT), but seismic data confirmed that the yield was less than 1 KT.53 Radioactive debris
indicates that the explosion was a nuclear test, and that a plutonium device was used.54 It is
widely believed that the warhead design was an implosion device.55 Uncertainties remain about
when the plutonium used for the test was produced and how much plutonium was in the device,
although a prominent U.S. nuclear scientist has estimated that North Korea likely used
approximately 6 kg of plutonium for the test.56
The test’s low yield may not have been a failure. Another possibility is that the test’s low yield
was intentional—a sophisticated device designed for a Nodong medium range missile.
Alternatively, a low yield could have been intended to avoid radioactive leakage from the test site
or to limit the amount of plutonium used.57
The May 25, 2009, Test
The DPRK announced on May 25, 2009, that it had successfully conducted another underground
nuclear test. An official North Korean news release said that this test was “on a new higher level
in terms of its explosive power and technology of its control and the results of the test helped
satisfactorily settle the scientific and technological problems arising in further increasing the
power of nuclear weapons.” This may be a reference to design problems associated with the low
50 See also CRS Report RL33709, North Korea’s Nuclear Test: Motivations, Implications, and U.S. Options, by Emma
Chanlett-Avery and Sharon Squassoni.
51 “Analysis of air samples collected on October 11, 2006 detected radioactive debris which confirms that North Korea
conducted an underground nuclear explosion in the vicinity of P.unggye on October 9, 2006. The explosion yield was
less than a kiloton.” ODNI News Release No. 19-06, at http://www.dni.gov/announcements/20061016_release.pdf.
52 By comparison, a simple plutonium implosion device normally would produce a larger blast, perhaps 5 to 20 kilotons
(KT). The first nuclear tests conducted by other states range from 9 KT (Pakistan) to 60 KT (France), but tests by the
United States, China, Britain, and Russia were in the 20 KT range.
53 Mark Mazzetti, “Preliminary Samples Hint at North Korean Nuclear Test,” New York Times, October 14, 2006, at
http://www.nytimes.com/2006/10/14/world/asia/14nuke.html.
54 Thom Shanker and David Sanger, “North Korean fuel identified as plutonium,” New York Times, October 17, 2006,
at http://www.nytimes.com/2006/10/17/world/asia/17diplo.html. A debate on this issue can be found in the November
2006 issue of Arms Control Today, at http://armscontrol.org/act/2006_11/tech.asp#Sidebar1.
55 Implosion devices, which use sophisticated lenses of high explosives to compress fissile material, are generally
thought to require testing, although the CIA suggested in 2003 that North Korea could validate a simple fission nuclear
weapons design using extensive high explosives testing. CIA response to questions for the record, August 18, 2003,
submitted by the Senate Select Committee on Intelligence, at http://www.fas.org/irp/congress/2003_hr/021103qfr-
cia.pdf.
56 Siegfried Hecker, “Report on North Korean Nuclear Program,” Center for International Security and Cooperation,
Stanford University, November 15, 2006.
57 Ibid. Also see Peter Hayes, Jungmin Kang, “Technical Analysis of the DPRK Nuclear Test,” Nautilus Institute,
October 22, 2006, http://www.nautilus.org/fora/security/0689HayesKang.html.
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yield of the 2006 test. A North Korean official statement had threatened on April 29, 2009, that it
would conduct “nuclear tests” to bolster its deterrent.58
The U.S. Geologic Survey registered an underground blast on May 25 with a seismic magnitude
of the event as 4.7 on the Richter scale.59 The Directorate of National Intelligence released a
statement on June 15 saying, “The U.S. Intelligence Community assesses that North Korea
probably conducted an underground nuclear explosion in the vicinity of P'unggye on May 25,
2009. The explosion yield was approximately a few kilotons. Analysis of the event continues.”60
Additional analysis will also be needed to determine the device’s design and how much nuclear
material was used. In contrast to 2006, no radioactive noble gases have been detected by
international monitoring stations and no national governments have announced such data.61 It is
possible that North Korea may have been able to contain the release of these gases and particles
from the test site. This data can provide not only evidence of a test, but potentially also
information on the type of weapon detonated.62
Delivery Systems
Although former Defense Intelligence Agency (DIA) Director Lowell Jacoby told the Senate
Armed Services Committee in April 2005 that North Korea had the capability to arm a missile
with a nuclear device, Pentagon officials later backtracked from that assessment. A DNI report to
Congress says that “North Korea has short and medium range missiles that could be fitted with
nuclear weapons, but we do not know whether it has in fact done so.”63 North Korea has several
hundred short-range Scud-class and medium range No Dong-class ballistic missiles, and is
developing an intermediate range ballistic missile. The Taepo-Dong-2 that was tested
unsuccessfully in July 2006 would be able to reach the continental United States if it becomes
operational. DNI assessed in 2008 that the Taepo-Dong-2 has the potential capability to deliver a
nuclear-weapon-sized payload to the United States, but that absent successful testing the
likelihood of this is low.64 A launch of a Taepo-Dong 2 missile as part of a failed satellite launch
in April 2009 traveled further than earlier unsuccessful launches but still did not achieve a
complete test.
It is possible that Pakistani scientist A.Q. Khan may have provided North Korea the same
Chinese-origin nuclear weapon design he provided to Libya and Iran. Even though that design
was for an HEU-based device, it would still help North Korea develop a reliable warhead for
ballistic missiles—small, light, and robust enough to tolerate the extreme conditions encountered
58 “UNSC Urged to Retract Anti-DPRK Steps,” KCNA, April 29, 2009, http://www.kcna.co.jp/item/2009/200904/
news29/20090429-14ee.html.
59 http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2009hbaf.php.
60 Statement by the Office of the Director of National Intelligence on North Korea’s Declared Nuclear Test on May 25,
2009, http://www.dni.gov/press_releases/20090615_release.pdf.
61 http://www.ctbto.org/press-centre/highlights/2009/experts-sure-about-nature-of-the-dprk-event/.
62 See also “Factfile: underground nuclear testing,” BBC News, May 26, 2009, http://news.bbc.co.uk/2/hi/asia-pacific/
6033893.stm.
63 Unclassified Report to Congress on Nuclear and Missile Programs of North Korea, Office of the Director of National
Intelligence, August 8, 2007. Also see CRS Report RS21473, North Korean Ballistic Missile Threat to the United
States, by Steven A. Hildreth.
64 Annual Threat Assessment of the Director of National Intelligence for the Senate Select Committee on Intelligence,
February 5, 2008, at http://www.dni.gov/testimonies/20080205_testimony.pdf.
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through a ballistic trajectory. Learning more about what is needed for miniaturization of warheads
for ballistic missiles could have been the goal of North Korea’s testing a smaller nuclear device.65
Doctrine and Intent
U.S. officials in their threat assessments have described the North Korean nuclear capabilities as
being more for deterrence and coercive diplomacy than for war fighting, and assess that
Pyongyang most likely would “not attempt to use nuclear weapons against U.S. forces or territory
unless it perceived the regime to be on the verge of military defeat and risked an irretrievable loss
of control.”66 Statements by North Korean officials emphasize that moves to expand their nuclear
arsenal are in response to perceived threats by the United States against the North Korean
regime.67 Nuclear weapons also give North Korea leverage in diplomatic negotiations, and
threatening rhetoric often coincides with times of crisis or transitions in negotiations. In January
2008, a North Korean media report stated that the country “will further strengthen our war
deterrent capabilities in response to U.S. attempts to initiate nuclear war,” to express its
displeasure that it had not yet been removed from the U.S. terrorism list.68 Statements from
Pyongyang in January 2009 may also be part of a strategy to increase leverage in nuclear talks,69
or could indicate an increasing role for the North Korean military in nuclear policy making.70 A
spokesman for North Korea’s General Staff said on April 18, 2009 that the revolutionary armed
forces “will opt for increasing the nation’s defense capability including nuclear deterrent in every
way.”71 At the same time, the DPRK issues periodic statements, such as its 2010 New Year’s
address stating its dedication to achieving a nuclear-free Korean Peninsula through negotiations.
Steps Toward Denuclearization Under the Six
Party Talks
In September 2005, North Korea agreed to abandon “all nuclear weapons and existing nuclear
programs,” but implementation of this goal was stalled.72 The October 9, 2006, nuclear test is
seen as a catalyst in uniting the other members of the Six Party Talks to toughen their stance
towards North Korea, and as a turning point in Pyongyang’s attitude. UN Security Council
65 “Technical Perspective on North Korea’s Nuclear Test: A Conversation between Dr. Siegfried Hecker and Dr. Gi-
Wook Shin,” Stanford University website, October 10, 2006, at http://aparc.stanford.edu/news/
technical_perspective_on_north_koreas_nuclear_test_a_conversation_between_dr_siegfried_hecker_and_dr_giwook_s
hin_20061010//.
66 Annual Threat Assessment of the Director of National Intelligence for the Senate Select Committee on Intelligence,
February 5, 2008, at http://www.dni.gov/testimonies/20080205_testimony.pdf.
67 See, for example, North Korea’s statement of February 10, 2005, at http://news.bbc.co.uk/2/hi/asia-pacific/
4252515.stm.
68 “North Korea says nuclear declaration submitted,” Reuters, January 4, 2008.
69 Blaine Harden, “With Obama in the White House, North Korea Steps Up Big Talk,” Washington Post, February 3,
2009.
70 See “North Korea” section of CRS Report R40439, Nuclear Weapons R&D Organizations in Nine Nations,
coordinated by Jonathan Medalia.
71 “DPRK military warns against sanctions for rocket launch,” Xinhua, April 18, 2008.
72 Joint Statement of the Fourth Round of Six Party Talks, Beijing, September 19, 2005, at http://www.state.gov/r/pa/
prs/ps/2005/53490.htm.
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Resolution 1718 calls on North Korea to abandon its nuclear weapons in a “complete, verifiable,
and irreversible manner.”73 In February 2007, as part of implementation of the September 2005
Joint Statement, North Korea committed to disable all nuclear facilities and provide a “complete
and correct” declaration of all its nuclear programs.74
Disablement
The October 2007 Six-Party joint statement said the United States would lead disablement
activities and provide the initial funding for those activities.75 Disablement indicates a physical
measure to make it difficult to restart operation of a facility while terms are being worked out for
its eventual dismantlement. U.S. officials said that their aim was a disablement process that
would require a 12-month time period to start up the facility again.76 The Six Parties agreed to 11
discrete steps to disable the three main Yongbyon facilities related to North Korea’s plutonium
program (nuclear fuel fabrication plant, plutonium reprocessing plant, and 5-megawatt
experimental nuclear power reactor).77 The disablement process began in early November 2007
and continued through April 2009. The most time-consuming step was the removal of the
irradiated fuel from the reactor to storage in an adjacent cooling pond.78 A reported eight out of
eleven steps were completed (see Table 1).79
Table 1. Disablement Steps at Yongbyon, DPRK
Step Facility Status
Discharge of 8000 spent fuel rods
5-megawatt reactor
6,400 completed as of April 2009
to the spent fuel pool
Removal of control rod drive
5-megawatt reactor
To be done after spent fuel removal
mechanisms
completed
Removal of reactor cooling loop
5-megawatt reactor
Tower demolished June 26, 2008
and wooden cooling tower
interior structure
Disablement of fresh fuel rods
Fuel fabrication facility
Not agreed to by North Korea;
consultations held Jan. 2009 with
South Korea on possibility of
purchase
Removal and storage of 3 uranium
Fuel fabrication facility
Completed
ore concentrate dissolver tanks
73 United Nations Security Council Resolution 1718, October 14, 2006, at http://daccessdds.un.org/doc/UNDOC/GEN/
N06/572/07/PDF/N0657207.pdf?OpenElement.
74 “Denuclearization Action Plan,” February 13, 2007, at http://merln.ndu.edu/archivepdf/northkorea/state/80479.pdf.
75 Second Phase Actions for the Implementation of the September 2005 Joint Statement, October 3, 2007, at
http://www.state.gov/r/pa/prs/ps/2007/oct/93223.htm.
76 On-the-Record-Briefing, U.S. Assistant Secretary of State Christopher Hill, October 3, 2007, at
http://www.state.gov/p/eap/rls/rm/2007/93234.htm.
77 “North Korea ‘Agrees to Nuclear Disablement Procedure,’” Chosun Ilbo, October 27, 2007.
78 David Albright and Paul Brannan, “Disabling DPRK Nuclear Facilities,” United States Institute of Peace Working
Paper, October 23, 2007.
79 See charts at “North Korean Disablement Actions,” Arms Control Today, October 2008; “Disablement Actions,”
National Committee on North Korea website.
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Step Facility Status
Removal and storage of 7 uranium
Fuel fabrication facility
Completed
conversion furnaces, including
storage of refractory bricks and
mortar sand
Removal and storage of both
Fuel fabrication facility
Completed
metal casting furnaces and vacuum
system, and removal and storage
of 8 machining lathes
Cut cable and remove drive
Reprocessing facility
Completed
mechanism associated with the
receiving hot cell door
Cut two of four steam lines into
Reprocessing facility
Completed
reprocessing facility
Removal of drive mechanisms for
Reprocessing facility
Completed
the fuel cladding shearing and
slitting machines
Removal of crane and door
Reprocessing facility
Completed
actuators that permit spent fuel
rods to enter the reprocessing
facility
Source: “North Korean Disablement Actions,” Arms Control Today, October 2008; “Disablement Actions,”
National Committee on North Korea website; Siegfried Hecker, “Denuclearizing North Korea,” Bulletin of the
Atomic Scientists, May/June 2008.
North Korea periodically slowed the pace of spent fuel rod removal at Yongbyon to show its
displeasure over other aspects of the Six-Party agreements.80 For example, in June 2008,
Pyongyang said that while 80% of the disablement steps had been completed, only 36% of energy
aid had been delivered.81 North Korea again delayed disablement work in August, September, and
October 2008, and those instances appear to have been linked to disputes over when the U.S.
would remove the DPRK from its State Sponsors of Terrorism List and negotiations over
verification measures. After the U.S. removed the SST designation, disablement work resumed in
October 2008, and continued until North Korea halted the process in April 2009.
The steps that were not completed in disabling the Yongbyon facilities as part of phase 2 of the
Six-Party Talks are: completing the removal of the spent fuel rods from the 5 megawatt reactor;
removing the control rod drive mechanism (after all rods are removed); and disabling or
removing from the country the fresh fuel rods at the site. As of early April 2009, approximately
80% or 6,400 of the 8,000 spent fuel rods had been moved from the reactor to the cooling pond.82
Pyongyang issued statements saying it had itself removed the remaining fuel rods from the
reactor to prepare for reprocessing.
In addition, the North Korea possesses 2,400 5-MWt fresh fuel rods and 12,000 50-MWt fresh
fuel rods in storage at Yongbyon. A technical delegation from South Korea visited the facility in
January 2009 to consider possibilities for removing the fuel rods. Another option discussed was to
80 “N. Korea ‘Slowing Disablement of Nuclear Facilities,” Chosun Ilbo, January 29, 2008.
81 Lee Chi-dong, “N Korea Complains About Slow Provision of Energy Aid,” Yonhap News, June 5, 2008.
82 “N. Korea can produce plutonium for 1.5 bombs in 6 months: expert,” Kyodo News, April 25, 2009.
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bend them so they could not be readily used in the reactor.83 It is not clear whether North Korea
had agreed to disablement or removal of the fresh fuel, and then balked, or whether it never had
agreed to this measure.
Reversing Disablement
The North Korean Foreign Ministry said on April 25, 2009, that it had restarted its reprocessing
facility, but there has been no way to independently verify this. North Korea said in November
2009 that it had reprocessed the 8,000 spent fuel rods in its possession by the end of August.
The extent to which the Yongbyon facilities had been disabled was first tested in September 2008
when North Korea halted international monitoring at the reprocessing facility, moved some
equipment out of storage, and threatened to begin reprocessing again.84 This temporary reversal
was corrected and equipment moved back to storage by November 2008. Taking into account the
need to test the facility (e.g., for leaks and cracks in the piping) and introduce chemicals, experts
estimated that restarting the reprocessing plant could take approximately six to eight weeks,
although this timeline might be shorter since some initial work may have been done in September
2008. It would then take approximately three to four months to reprocess the spent fuel rods now
in storage at Yongbyon, resulting in 7 kg to 8 kg of plutonium. This would be enough for at least
one nuclear weapon.85 According to reports, disablement was limited to the “front-end,” where
spent fuel is loaded, at the reprocessing facility for technical reasons related to the safe disposal
of the high-level waste in the facility.86
In order to produce additional plutonium, the North Koreans would need to restore their 5-MWt
reactor or build a new reactor. Timelines for restoring the 5-MWt reactor are uncertain, although
experts estimate between six months and one year. Rebuilding the cooling tower, which was
destroyed in June 2008, could take approximately six months, but other venting solutions for the
reactor could be possible. Additionally, this aging reactor may be in need of additional parts or
repair. The fuel fabrication facility would have to be restored to produce additional fuel. Former
Director of the Los Alamos National Laboratories, Siegfried Hecker, has said that while
significant work is needed to do so, North Korea could restore operations at the 5 megawatt
reactor and fuel fabrication facility without foreign equipment or materials, and could do so in
approximately six months. After the facilities were operating, they could produce approximately 6
kg of plutonium per year.87 Significant future growth in North Korea’s arsenal would be possible
only if larger reactors were completed and operating, and would also depend on any progress in
the reported uranium enrichment program.
83 “MOFAT Reveals North Korean Fuel Rod Images,” Daily North Korea, February 4, 2009. http://www.dailynk.com/
english/read.php?cataId=nk03100&num=4516.
84 IAEA Press Release, “IAEA Removes Seals at Yongbyon,” September 24, 2008.
85 Peter Crail, “North Korea Moves to Restart Key Nuclear Plant,” Arms Control Today, October 2008.
86 For a discussion of the pro’s and con’s see sidebar “A Diplomatic and Technological Cocktail,” Bulletin of the
Atomic Scientists, May/June 2008, p.49.
87 “North Korea can produce plutonium for 1.5 bombs in 6 months,” Japan Economic Newswire, April 25, 2009.
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Declaration
The required content of a “complete and correct” declaration as promised under the Six Party
negotiations evolved over time. Bush administration officials in fall 2007 said they expected the
declaration to include a full declaration of the separated weapons-grade plutonium that has
already been produced, as well as full disclosure of uranium enrichment activities.88 The North
Korean Foreign Ministry said on January 4, 2008 that it had notified the United States of the
content of its declaration in November 2007. However, Assistant Secretary Hill said that the two
sides had discussed what was expected to be in a declaration, and “it was clearly not a complete
and correct declaration.”89 At that time, North Korea reportedly suggested it would declare 30 kg
of separated plutonium in its declaration, a lower number than U.S. officials have alluded to (see
above) but in the range of some analyses.90 The United States has said that “materials, facilities
and programs” need to be included in a declaration. In addition to plutonium stocks, North Korea
agreed to “address concerns about a uranium enrichment program but denies that it has one” (see
below). Other outstanding issues are nuclear proliferation activities and warhead information.
North Korea has said it would not include warhead information at this stage. Once the original
December 31 deadline for submission of the declaration had passed, U.S. officials emphasized
that the completeness of the document was more important than its timing. U.S. officials also
made statements in early 2008 that removal from sanctions lists would only happen after a
complete declaration was submitted to the six parties.
According to press reports,91 at a bilateral meeting in Singapore in April 2008, the United States
and North Korea agreed to a formulation in which North Korea would include its plutonium
production activities in a formal declaration, and the enrichment and proliferation issues would be
dealt with separately in a secret side agreement in which North Korea would “acknowledge” the
U.S. concerns over North Korean proliferation to Syria without confirming or denying them. This
agreement is also supposed to have included a pledge by North Korea that it would not engage in
any future nuclear proliferation. Administration officials in spring 2008 emphasized that ending
plutonium production and tallying the plutonium stockpile were the highest priorities. However,
concerns were raised in the Congress and elsewhere by those skeptical of this approach, with
some observers wanting assurance that the North Korean declaration of its plutonium stockpile
would be adequately verified before the United States removed them from the State Sponsors of
Terrorism List.
On May 8, 2008, North Korean officials gave State Department Korean Affairs Director Sung
Kim approximately 19,000 pages of documentation related to its nuclear program. According to a
88 On-The-Record Briefing: Assistant Secretary of State for East Asian and Pacific Affairs and Head of the U.S.
Delegation to the Six-Party Talks Christopher R. Hill, October 3, 2007, at http://www.state.gov/p/eap/rls/rm/2007/
93234.htm.
89 Joint Press Availability, Assistant Secretary of State Christopher R. Hill, January 7, 2008. http://www.state.gov/p/
eap/rls/rm/2008/01/98756.htm.
90 David Albright, Paul Brannan, and Jacqueline Shire, “North Korea’s Plutonium Declaration: A Starting Point for an
Initial Verification Process,” The Institute for Science and International Security, January 10, 2008. http://www.isis-
online.org/publications/dprk/NorthKoreaDeclaration10Jan2008.pdf.
91 See, for example, Helene Cooper, “Past Deals by N. Korea May Face Less Study,” The New York Times, April 18,
2008. http://www.nytimes.com/2008/04/18/washington/18diplo.html?_r=2&adxnnl=1&oref=slogin&ref=world&
adxnnlx=1208545358-9gpsLj35wtiPmoT8RHM6mQ and Glenn Kessler, “U.S. Ready to Lift Sanctions on North
Korea,” The Washington Post, April 11, 2008. http://www.washingtonpost.com/wp-dyn/content/article/2008/04/10/
AR2008041004082.html?nav=emailpage.
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State Department fact sheet, the documents consist of operating records for the five-megawatt
reactor [5-MW(e)] and fuel reprocessing plant at the Yongbyon nuclear complex, dating back to
1986. They reportedly include reactor operations and information on all three reprocessing
campaigns undertaken by North Korea.92 As referenced above, press reports indicated that U.S.
personnel had found traces of highly-enriched uranium on these documents, raising new doubts
about the extent of North Korea’s uranium enrichment program at a sensitive juncture in the
negotiations.93
On June 26, 2008, North Korea submitted a declaration of its nuclear programs to China, the
Chair of the Denuclearization Working Group. Ambassador Christopher Hill said in testimony to
Congress that the “declaration package” addresses “its plutonium program, and acknowledged
our concerns about the DPRK’s uranium enrichment and nuclear proliferation activities,
specifically with regard to Syria.”94 Press reports have said that North Korea submitted a list of
nuclear sites and declared 37 kg of plutonium in the 60-page document. The confidential message
acknowledging U.S. concerns about uranium enrichment and proliferation activities was received
days earlier.95 In response, also on June 26, 2008, President Bush announced that the Trading with
the Enemy Act (TWEA) would no longer apply to North Korea and notified Congress of his
intent to remove North Korea’s designation as a State Sponsor of Terrorism (SST) after the
required 45-day wait period.96 The day after the declaration was submitted the U.S. assisted North
Korea in destroying the cooling tower at the 5-megawatt reactor at Yongbyon. Subsequent
verification issues are discussed below.
Verification
IAEA inspectors returned to North Korea in July 2007 to monitor and verify the shut-down,
install seals, and monitor facilities at the Yongbyon nuclear complex, and had a continuous
presence there until mid-April 2009.97 In his September 10, 2007, statement to the IAEA Board of
Governors, Director General Mohamed ElBaradei stated that the IAEA was able to verify the
shutdown of nuclear facilities, including the nuclear fuel fabrication plant, radio-chemical
laboratory (reprocessing plant), and the 5MWe experimental nuclear power reactor. Inspectors
were also monitoring the halt in construction of the 50-megawatt nuclear power plant at
Yongbyon and the 200-megawatt nuclear power plant in Taechon.98 The United States has
contributed $1.8 million as the U.S. voluntary contribution and Japan has contributed $500,000 to
the IAEA for their work in North Korea.99 In the future, the IAEA may be called on to investigate
92 “Update on the Six-Party Talks,” State Department Fact Sheet, May 10, 2008. http://www.state.gov/r/pa/prs/ps/2008/
may/104558.htm.
93 Glenn Kessler, “New Data Found On North Korea’s Nuclear Capacity; Intelligence on Enriched Uranium Revives
Questions About Weapons,” The Washington Post, June 21, 2008.
94 Statement of Christopher R. Hill, Assistant Secretary of State, Bureau of East Asian and Pacific Affairs, U.S.
Department of State, to the Senate Committee on Armed Services, July 31, 2008.
95 Glenn Kessler, “Message to US Preceded North Korean Nuclear Declaration,” The Washington Post, July 2, 2008.
96 http://www.whitehouse.gov/news/releases/2008/06/20080626-4.html; http://www.state.gov/r/pa/prs/ps/2008/jun/
106281.htm.
97 “IAEA Team Confirms Shut Down of DPRK Nuclear Facilities,” IAEA press release, July 18, 2007, at
http://www.iaea.org/NewsCenter/PressReleases/2007/prn200712.html.
98 GOV/2007/45-GC(51)/19, August 17, 2007.
99 Statement of Christopher R. Hill Assistant Secretary, Bureau of East Asian and Pacific Affairs, Department of State
before the House Committee on Foreign Affairs, Subcommittee on Asia, the Pacific and the Global Environment and
(continued...)
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North Korea’s past nuclear program in addition to monitoring activities; however, to date, its role
has been limited to monitoring the shut-down of Yongbyon facilities. The IAEA’s role in
disablement and future dismantlement efforts has yet to be clearly determined. Some analysts
recommend an observer role for the IAEA during disablement steps and continued IAEA
monitoring to boost international confidence in the process.100 The United States and North Korea
reportedly agreed on an “consultative and support” role for the IAEA in future verification in
October 2008.101
After IAEA inspectors were expelled from North Korea in 2002, information about North Korea’s
nuclear weapons production depended on remote monitoring and defector information, with
mixed results. Satellite images correctly indicated the start-up of the 5MWe reactor, but gave no
details about its operations. Satellites also detected trucks at Yongbyon in late January 2003, but
could not confirm the movement of spent fuel to the reprocessing plant;102 imagery reportedly
detected activity at the reprocessing plant in April 2003, but could not confirm large-scale
reprocessing;103 and satellite imagery could not peer into an empty spent fuel pond, which was
shown to U.S. visitors in January 2004. North Korean officials stated in 2004 that the
reprocessing campaign was conducted continuously (four six-hour shifts). U.S. efforts to detect
Krypton-85 (a by-product of reprocessing) reportedly suggested that some reprocessing had taken
place, but were largely inconclusive. Even U.S. scientists visiting Pyongyang in January 2004
could not confirm North Korean claims of having reprocessed the spent fuel or that the material
shown was in fact plutonium. These are some of the uncertainties verification measures will seek
to answer.
Verification received increased attention in the Six Party process beginning in spring 2008.
Statements made by President Bush and Secretary of State Rice in June 2008 further
demonstrated that the U.S. administration was linking SST removal with progress on verification
issues.104 U.S. officials have said there have been spoken agreements with the North Koreans
saying that the only way the declaration can be deemed “complete and correct” is if it verifiable.
The State Department said in a June 26 fact sheet that by submitting the declaration, North Korea
had “begun to fulfill its declaration commitment.” The fact sheet also stated that a comprehensive
verification regime would include “short notice access to declared or suspect sites related to the
North Korean nuclear program, access to nuclear materials, environmental and bulk sampling of
materials and equipment, interviews with personnel in North Korea, as well as access to
additional documentation and records for all nuclear related facilities and operations.” It also said
that the actual rescission of North Korea’s designation as a State Sponsor of Terrorism will occur
only after “the Six Parties reach agreement on acceptable verification principles and an
(...continued)
Subcommittee on Terrorism, Nonproliferation and Trade, Joint Hearing on the North Korea Six-Party Process, October
25, 2007.
100 North Korea reportedly did not want the IAEA involved and wanted the United States to do the disabling. Albright
and Brannan, ibid.
101 “U.S.-North Korea Understandings on Verification,” October 11, 2008. http://2001-2009.state.gov/r/pa/prs/ps/2008/
oct/110924.htm.
102 “Reactor Restarted, North Korea Says,” Washington Post, February 6, 2003.
103 “US Suspects North Korea Moved Ahead on Weapons,” New York Times, May 6, 2003.
104 “President Bush Discusses North Korea,” White House press release, June 26, 2008; Condoleezza Rice, “U.S.
Policy Toward Asia,” Heritage Foundation speech, June 18, 2008.
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acceptable verification protocol; the Six Parties have established an acceptable monitoring
mechanism; and verification activities have begun.”105
On July 12, 2008, the Six Parties agreed unanimously to principles for a “verification
mechanism” for the denuclearization of the Korean Peninsula, to be detailed by the
denuclearization working group.106 Thereafter, U.S. negotiators submitted a proposed verification
protocol to North Korea called the “Verification Measures Discussion Paper” which outlined
extensive measures to verify all aspects of North Korea’s nuclear programs, including plutonium
production, uranium enrichment, weapons, weapons production and testing, and proliferation
activities.107 North Korea reportedly submitted a counter-proposal that objected to provisions
related to inspections at undeclared facilities and the taking of samples.
The 45-day wait period for the SST List removal ended on August 11, 2008, but the
administration did not take action. On August 26, the North Korean news agency announced it
had suspended disablement activities at Yongbyon as of August 14 since the United States had not
removed it from the terrorism list. The North Korean Foreign Ministry statement said that the
agreement had been to delist North Korea once it had submitted a declaration of its nuclear
programs, not once verification measures had been agreed upon. It said, “As far as the
verification is concerned, it is a commitment to be fulfilled by the six parties at the final phase of
the denuclearization of the whole Korean Peninsula according to the September 19 joint
statement.... All that was agreed upon at the present phase was to set up verification and
monitoring mechanisms within the framework of the six parties.”108 The statement also threatened
to restore facilities at Yongbyon.
On Monday, September 22, 2008, North Korea asked the International Atomic Energy Agency
(IAEA) personnel monitoring the shut-down of facilities at the Yongbyon nuclear complex to
remove the seals and surveillance equipment from the plutonium reprocessing plant. North Korea
informed the IAEA that inspectors would no longer have access to that facility. IAEA inspectors
and U.S. Department of Energy personnel located at Yongbyon were not expelled from the
Yongbyon site, and other monitoring and inspection activities related to disablement continued.
However, North Korea told the IAEA that it planned to “introduce nuclear material to the
reprocessing plant in one week’s time.”109
These actions were reversed when, in early October, the US and North Korea agreed on a
Averification mechanism@ to determine the accuracy of the DPRK’s declaration of its plutonium
production. Ambassador Hill traveled to Pyongyang October 2-3 for further bilateral talks on the
verification agreement. As a result of these talks, the US and DPRK reached agreement on
verification measures. Although the document has not yet been made public, according to State
Department officials North Korea has agreed to: the US taking samples out of country for review;
visits to all declared sites and to undeclared sites by mutual consent; participation of South Korea
105 “North Korea: Presidential Action on State Sponsor of Terrorism (SST) and the Trading with the Enemy Act
(TWEA),” State Department Fact Sheet, June 26, 2008. http://www.state.gov/r/pa/prs/ps/2008/jun/106281.htm.
106 Press Communique of the Heads of Delegation Meeting of the Sixth Round of the Six-Party Talks, Beijing, July 12,
2008. http://www.mofa.go.jp/region/asia-paci/n_korea/6party/press0807.html.
107 This paper was made public by the Washington Post. Glenn Kessler, “Far-Reaching U.S. Plan Impaired North
Korea Deal,” The Washington Post, September 26, 2008.
108 “Foreign Ministry’s Spokesman on DPRK’s Decision to Suspend Activities to Disable Nuclear Facilities,” KCNA,
August 27, 2008. http://www.kcna.co.jp/index-e.htm.
109 http://www.iaea.org/NewsCenter/PressReleases/2008/prn200813.html.
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and Japan in verification; and a consultative role for the IAEA.110 They also agreed that “all
measures contained in the Verification Protocol will apply to the plutonium-based program and
any uranium enrichment and proliferation activities.” According to the State Department’s fact
sheet on the agreement, the measures are “codified in a joint document between the United States
and North Korea and certain other understandings.” Many observers interpret “other
understandings” as referring to verbal agreements or separate documents, but neither the United
Stats nor North Korea have made this clear. The United States removed North Korea from the
State Sponsors of Terrorism List on October 11.
Then-Presidential candidate Barack Obama issued a statement after the October 11, 2008 SST list
removal that emphasized strong verification measures:
If North Korea refuses to permit robust verification, we should lead all members of the Six
Party talks in suspending energy assistance, re-imposing sanctions that have recently been
waived, and considering new restrictions. Our objective remains the complete and verifiable
elimination of North Korea’s nuclear weapons programs. This must include getting clarity on
North Korea’s efforts to enrich uranium and its proliferation of nuclear technology abroad.111
Key concerns about the details of the tentative verification agreement as well as whether North
Korea had actually agreed to the provisions surfaced soon after the announcement. For example,
while State Department officials said that North Korea agreed to removal of samples from the
country for analysis, North Korea statements in press reports contradicted this.112 The Six Parties
were unable to reach agreement on a codified version of the verification measures in their
December 2008 meeting, as North Korea appeared to reject inclusion of sampling provisions.
As described above, verification and monitoring activities in North Korea ended when
Pyongyang asked U.S. and international inspectors to leave the country on April 14, 2009.113
Future Considerations
The DPRK committed in 2005 to abandoning “all nuclear weapons and existing nuclear
programs” and to returning to the Non-Proliferation Treaty and IAEA safeguards at an early
date.114 If the DPRK decides to return to the Six Party talks and uphold these commitments, there
will be a number of issues that have not yet been resolved.
The next stage, after disablement, was to have been the decommissioning and dismantlement of
the weapons production facilities. The terms for this work still need to be negotiated. This stage
may include a return of IAEA monitoring of nuclear material stocks (including weapons-usable
separated plutonium) and verification of actual weapons dismantlement. The question of
dismantling North Korea’s nuclear warheads has not yet been addressed directly, although the
110 See October 11, 2008 State Department Press Statement http://2001-2009.state.gov/r/pa/prs/ps/2008/oct/110924.htm
and Fact Sheet http://2001-2009.state.gov/r/pa/prs/ps/2008/oct/110924.htm.
111 Statement of Senator Barack Obama on the Agreement with North Korea, October 11, 2008.
112 “SKorea to press for sampling at NKorean nuke plants,” Agence France Presse, November 14, 2008.
http://news.yahoo.com/s/afp/20081113/wl_asia_afp/nkoreanuclearweaponsskoreaus.
113 “IAEA Inspectors Asked to Leave the Democratic People’s Republic of Korea,” IAEA Press Release, April 14,
2009, http://www.iaea.org/NewsCenter/PressReleases/2009/prn200903.html.
114 http://2001-2009.state.gov/r/pa/prs/ps/2005/53490.htm.
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September 2005 joint statement commits North Korea to abandon all nuclear weapons. Critics
have raised concerns about the lack of clear verification provisions for these steps and the
omission of specific references to key issues such as fissile materials, warheads, the reported
uranium enrichment program, the nuclear test site, and nuclear proliferation activities and history
(such as possible nuclear transfers to Syria).
Some analysts have proposed that the United States should be ready to implement cooperative
threat reduction (CTR)-style programs in North Korea, as were created for the former Soviet
Union.115 These might include the redirection of North Korean nuclear weapon scientists to
peaceful work.116 North Korean officials have said that they are interested in eventually
reorienting the Yongbyon workforce to the peaceful use of nuclear energy.117 This could include
research, medical and industrial applications, and not necessarily a nuclear power program.
Proliferation Issues118
Concerns persist that North Korea will continue its proliferation of missile and nuclear
technology for a variety of motivations, including financial profit, joint exchange of data to
develop its own systems, and as part of the general provocative trend. According to DNI Admiral
Dennis Blair’s testimony to Congress, North Korea is known to have sold in the past ballistic
missiles and associated materials to “several Middle Eastern countries, including Iran, and, in our
assessment, assisted Syria with the construction of a nuclear reactor.”119 On the likelihood of
nuclear proliferation from the DPRK, the DNI assessed that
Pyongyang is less likely to risk selling nuclear weapons or weapons-quantities of fissile
material than nuclear technology or less sensitive equipment to other countries or non-state
actors, in part because it needs its limited fissile material for its own deterrent. Pyongyang
probably also perceives that it would risk a regime-ending military confrontation with the
United States if the nuclear material was used by another country or group in a nuclear strike
or terrorist attacks and the United States could trace the material back to North Korea. It is
possible, however, that the North might find a nuclear weapons or fissile material transfer
more appealing if its own stockpile grows larger and/or it faces an extreme economic crisis
where the potentially huge revenue from such a sale could help the country survive.
Due to concerns of proliferation and North Korea’s past track record, the Security Council
deliberations on a resolution condemning the May 2009 North Korean test focused on ways to
interdict North Korean shipments of missile and WMD-related technologies and prevent their
financing. U.N. Security Council Resolution 1874 calls on all states to “inspect, in accordance
with their national legal authorities and consistent with international law, all cargo to and from the
115 Joel Wit, Jon Wolfsthal, Choong-suk Oh, “The Six Party Talks and Beyond: Cooperative Threat Reduction in North
Korea,” CSIS Press, December 2005. http://www.csis.org/media/csis/pubs/051216_ctr.pdf.
116 David Albright, “Phased International Cooperation with North Korea’s Civil Nuclear Programs,” Institute for
Science and International Security, March 19, 2007. http://www.isis-online.org/publications/dprk/CivilNuclearNK.pdf.
117 “North Korea and Its Nuclear Program—A Reality Check,” A Report to Members of the Committee on Foreign
Relations, United States Senate, October 2008, S. Prt. 110-50.
118 Also see “Nuclear Collaboration with Iran and Syria” in CRS Report RL33590, North Korea’s Nuclear Weapons
Development and Diplomacy, by Larry A. Niksch, and “Clandestine Nuclear Program and the IAEA Investigation” in
CRS Report RL33487, Syria: Background and U.S. Relations, by Jeremy M. Sharp.
119 http://intelligence.senate.gov/090212/blair.pdf.
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DPRK, in their territory, including seaports and airports,” if that state has information that the
cargo is prohibited by UN Security Council Resolutions. This would include cargo related to
heavy arms (see UNSCR 1718 (8)(a)) and nuclear-related, ballistic missile-related, or other
WMD-related programs. The resolution also calls on states to inspect suspect vessels on the high
seas, with the consent of the flag state, and prohibits “bunkering services” for such shipments
such as refueling or servicing. This is significant because North Korea reportedly ships most
goods under its own flag, and typically uses small vessels that would need refueling. Reportedly
due to objections by Russia and China, the resolution does not authorize the use of force if a
North Korean vessel resists inspection.120 The resolution also has strict provisions regarding
financial services and transfer of funds through third parties, measures that may also help prevent
proliferation-related transfers. Resolution 1874 bans all arms transfers from North Korea, and all
arms transfers to North Korea except for small arms and light weapons (which require
notification).
In addition, South Korea announced it would join the Proliferation Security Initiative in response
to the test. This is a U.S.-led coordinating mechanism that is meant to guide international
cooperation in carrying out interdictions of proscribed WMD and missile-related goods.121 China
does not participate in PSI. Therefore, a key question for implementation of the Security Council
resolution will be China’s commitment to actual interdiction measures and willingness of others
to share sensitive information, particularly if Chinese firms are implicated, as has been the case in
the past. Also, there is little emphasis on airspace interdictions, which would be relevant, for
example, in the case of North Korean shipments passing over Chinese airspace on their way to
the Middle East. However, questions remain about the true commitment of China and others to
preventing WMD and missile-related transfers to and from North Korea, in particular because
North Korea has stated it views any interdiction as an “act of war.”
Issues for Congress
Funding122
Congress will have a clear role in considering U.S. funding for any future dismantlement of North
Korea’s nuclear facilities, as well as other inducements for cooperation as agreed in the Six Party
talks. U.S. assistance to nuclear disablement activities at Yongbyon was funded through the State
Department’s Nonproliferation and Disarmament Fund (NDF). The State Department paid the
North Korean government for the labor costs of disablement activities, and also paying for related
equipment and fuel. Approximately $20 million was approved for this purpose. NDF funds may
be used “notwithstanding any other provision of law” and therefore may be used to pay North
Korea. DOE’s National Nuclear Security Administration (NNSA) has been contributing its
personnel as technical advisors to the U.S. Six-Party delegation and as technical teams on the
ground at Yongbyon overseeing disablement measures. NNSA has estimated it spent
approximately $15 million in support of Phase Two (Yongbyon disablement) implementation.123
120 Blaine Harden, “North Korea Says It Will Start Enriching Uranium,” Washington Post, June 14, 2009.
121 For background on PSI, see CRS Report RL34327, Proliferation Security Initiative (PSI), by Mary Beth Nikitin.
122 For a detailed discussion, see CRS Report R40095, Foreign Assistance to North Korea, by Mark E. Manyin and
Mary Beth Nikitin.
123 Statement of William H. Tobey, National Nuclear Security Administration, U.S. Department of Energy, to the
(continued...)
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Congress has also provided funding for energy assistance to North Korea under the Six Party
Talks through the State Department’s Economic Support Fund.
Authority
Congress also plays a role in establishing legal authority for assistance to nuclear disablement and
dismantlement in North Korea. Section 102 (b) (the “Glenn Amendment” U.S.C. 2799aa-1) of the
Arms Export Control Act prohibits assistance to a non-nuclear weapon state under the NPT that
has detonated a nuclear explosive device. Due to this restriction, DOE funds cannot be spent in
North Korea without a waiver. Congress passed language in the FY2008 Supplemental
Appropriations Act (P.L. 110-252) that would allow the President to waive the Glenn Amendment
restrictions and that stipulates that funds may only be used for the purpose of eliminating North
Korea’s WMD and missile-related programs.124 If the President had exercised the Glenn
Amendment waiver authority, then DOE “will be able to procure, ship to North Korea, and use
equipment required to support the full range of disablement, dismantlement, verification, and
material packaging and removal activities that Phase Three will likely entail.”125 NNSA estimated
that this would cost over $360 million in FY2009 if verification proceeded and North Korea
agreed to the packaging and disposition of separated plutonium and spent fuel at Yongbyon.
Because North Korea conducted an underground nuclear test on May 25, 2009, the waiver may
no longer be issued under P.L. 110-252. The law stipulated that a nuclear test after the date of
enactment would nullify the waiver authority.126
Congress had expressed concern that the Department of Energy have enough funds available to
support the disablement of North Korea’s nuclear weapons arsenal and production capability. In
the FY2008 Consolidated Appropriations Act, the Committees on Appropriations provided DOE’s
NNSA with funding discretion to provide up to $10 million towards its activities in North Korea.
It also directs the Department to submit a supplemental budget request if additional resources are
required during FY2008.127 However, due to North Korean withdrawal from the Six Party talks,
Congress did not fund administration requests in the FY2009 Supplemental Appropriations or the
FY2010 Consolidated Appropriations Act. The State Department’s NDF, which did receive
funding, could be used for denuclearization assistance in the case of a breakthrough in the talks.
Beyond the Glenn amendment restrictions, Department of Defense funds must be specifically
appropriated for use in North Korea. Section 8045 of the FY2008 Defense Appropriations Act
says that “None of the funds appropriated or otherwise made available in this Act may be
obligated or expended for assistance to the Democratic People’s Republic of Korea unless
(...continued)
Senate Committee on Armed Services, July 31, 2008.
124 Similar language appeared in the Senate version of the FY2009 Duncan Hunter National Defense Authorization Act
(P.L. 110-417), but was not included in the House version. The final act includes it under “legislative provisions not
adopted” under Title XII, since the waiver authority was passed earlier in the FY2008 Supplemental. See joint
explanatory note: http://armedservices.house.gov/pdfs/fy09ndaa/FY09conf/
FY2009NDAAJointExplanatoryStatement.pdf.
125 Tobey testimony, ibid.
126 In P.L. 110-252 Sec. 1405 (b)(3), there is an exception for activities described in Subparas A or B of section102(b)1
of AECA. This includes “transfers to a non-nuclear weapon state a nuclear explosive device,” and “is a non-nuclear-
weapon state and either (i) receives a nuclear explosive device, or (ii) detonates a nuclear explosive device.”
127 See p. 50 of http://www.rules.house.gov/110/text/omni/jes/jesdivc.pdf.
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specifically appropriated for that purpose.” Section 8044 of the FY2009 Consolidated Security,
Disaster Assistance, and Continuing Appropriations Act, 2009 (P.L. 110-329) also contains this
language. However, authorization was given for CTR funds to be used globally. The FY2008
Defense Authorization Act specifically encourages “activities relating to the denuclearization of
the Democratic People’s Republic of Korea” as a potential new initiative for CTR work. Senator
Richard Lugar has proposed that the CTR program be granted “notwithstanding authority”128 for
this work since the Defense Department’s experience in the former Soviet Union, expertise and
resources could make it well-positioned to conduct threat reduction work in North Korea and
elsewhere. The Department of Defense did not work on recent disablement efforts, but there may
be a future role for DOD if North Korea in the future agrees to dismantlement work.
Policy Guidance
Congress may choose to influence the course of negotiations with North Korea through
legislation that limits or places requirements on U.S. diplomatic actions. For example, the North
Korean Counter-Terrorism and Non-Proliferation Act (H.R. 3650) introduced in the 110th
Congress called for certification by the President that North Korea has met a range of
nonproliferation and political benchmarks before the administration could lift any U.S.
sanctions.129 Congress could establish reporting requirements on progress, or condition
appropriations or disbursement to North Korea upon verification measures.130 Congress could
also be involved in other aspects of potential changes in U.S. relations with Pyongyang, such as
the monitoring of human rights issues, funding for further denuclearization steps including
verification provisions, and establishment of normalized ties once nuclear dismantlement has
been achieved. Congress also plays a role in setting sanctions policies, as in the bill Security
through Termination of Proliferation Act of 2009 (H.R. 485).
Author Contact Information
Mary Beth Nikitin
Analyst in Nonproliferation
mnikitin@crs.loc.gov, 7-7745
128 So that funds may be used “notwithstanding any other provision of law.” Senator Richard Lugar, Remarks to
National Defense University, October 2, 2008. http://lugar.senate.gov/record.cfm?id=304026&&.
129 This bill was introduced and referred to the House Committee on Foreign Affairs. H.R. 3650, September 25, 2007.
130 For example, see S.Res. 399.
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