Order Code 97-1007 F
Updated August 31, 2005
CRS Report for Congress
Received through the CRS Web
Nuclear Testing and Comprehensive Test
Ban: Chronology Starting September 1992
Specialist in National Defense
Foreign Affairs, Defense, and Trade Division
The Comprehensive Test Ban Treaty (CTBT) bans “any nuclear weapon test explosion or any other nuclear explosion.” It was opened for signature in September 1996.
In September 1997, President Clinton submitted it to the Senate, which rejected it in
October 1999. The Bush Administration has not requested Senate consideration of the
treaty. This report details actions on nuclear testing and the treaty starting with the most
recent U.S. test in September 1992. It complements CRS Issue Brief IB92099, Nuclear
Weapons: Comprehensive Test Ban Treaty and Nuclear Testing, which discusses earlier
history, issues, and current developments, and CRS Report RS20351, Comprehensive
Test Ban Treaty: Pro and Con, which presents arguments for and against the treaty.
This report will be updated; see the issue brief for interim updates.
09/23/92 — The United States conducted its most recent nuclear test, “Divider.”
10/02/92 — President Bush signed the FY1993 Energy and Water Development
Appropriations Act (P.L. 102-377); sec. 507 restricted U.S. nuclear
10/13/92 — Russia announced an extension of its test moratorium at least to mid-1993.
01/13/93 — President François Mitterrand said France would extend its test
moratorium as long as the United States and Russia did.
04/24/93 — At the Vancouver summit, Presidents Clinton and Yeltsin agreed that
negotiations on a multilateral test ban should begin soon.
07/03/93 — President Clinton announced his plan to continue the test moratorium
through September 1994 as long as no other nation tests.
08/10/93 — The Conference on Disarmament (CD) gave its Ad Hoc Committee on a
Nuclear Test Ban a mandate to negotiate a CTBT.
10/05/93 — China held the world’s first nuclear test since September 1992.
01/25/94 — The Conference on Disarmament opened its 1994 session in Geneva, with
negotiation of a CTBT its top priority.
03/15/94 — The United States extended its test moratorium through September 1995.
06/10/94 — China conducted an underground nuclear test.
Congressional Research Service ˜ The Library of Congress
09/26/94 — President Yeltsin, in an address to the U.N. General Assembly, said,
“Russia favors signing this treaty [the CTBT] next year.”
10/07/94 — China conducted an underground nuclear test.
01/24/95 — President Clinton said in his State of the Union address, “The United
States will lead the charge to extend indefinitely the Nuclear NonProliferation Treaty [and] to enact a comprehensive nuclear test ban.”
01/30/95 — President Clinton continued the U.S. moratorium until a CTBT enters into
force, assuming it is signed before September 30, 1996.
05/11/95 — The Nuclear Non-Proliferation Treaty Review and Extension Conference
agreed to extend that treaty indefinitely, and by reference called for
completing CTBT negotiations not later than 1996.
05/15/95 — China conducted a nuclear test, its fourth since September 1992.
06/13/95 — President Jacques Chirac announced that France would conduct eight
nuclear tests in the South Pacific between September 1995 and May 1996.
08/04/95 — The Senate tabled, 56 to 44, an amendment by Senator Exon and others
to delete $50 million for conducting hydronuclear tests (those producing
extremely low nuclear yield). The amendment was to S. 1026, the
FY1996 National Defense Authorization Bill.
08/10/95 — France announced that once it completed its nuclear test program, it would
support a CTBT that bans all nuclear tests of any yield.
08/11/95 — President Clinton announced his decision to pursue a “true zero yield”
CTBT, banning all nuclear tests regardless of yield, accompanied by six
“safeguards” to assure confidence in U.S. nuclear weapons under a CTBT.
08/17/95 — China conducted a nuclear test, its fifth since September 1992.
09/05/95 — France conducted a nuclear test, its first since 1991.
12/13/95 — A U.N. General Assembly resolution, passed 85-18, “strongly deplores”
current nuclear testing and “strongly urges” an immediate end to testing.
01/23/96 — In his State of the Union Address, President Clinton stated,”We must end
the race to create new nuclear weapons by signing a truly comprehensive
nuclear test ban treaty — this year.”
01/27/96 — France held the sixth nuclear test in its test series.
01/29/96 — President Jacques Chirac announced “the final end to French nuclear
03/07/96 — The Washington Times reported U.S. intelligence agencies have
ambiguous evidence that Russia may have conducted a nuclear test in
04/19/96 — President Yeltsin formally endorsed a zero-yield CTBT and reserved the
right to resume testing if Russia’s supreme interests are threatened. The
next day, the Group of Seven plus Russia expressed their commitment to
complete and sign a zero-yield CTBT by September 1996.
05/28/96 — Ambassador Jaap Ramaker of the Netherlands, Chairman of the
Conference on Disarmament’s Ad Hoc Committee on a Nuclear Test Ban,
tabled a draft text of a CTBT incorporating compromises on key
06/04/96 — France and the United States signed an agreement to share information
relevant to maintaining nuclear weapons.
06/08/96 — China held a nuclear test and declared that after one more test it would
join an international moratorium on nuclear explosions.
06/20/96 — India stated it would not sign a CTBT unless the five declared nuclear
weapon states agreed to a timetable to give up their nuclear weapons.
06/26/96 — The Senate tabled, 53-45, an amendment by Senators Kyl and Reid to the
FY1997 National Defense Authorization Bill to permit U.S. nuclear
testing after September 30, 1996, under certain conditions if the Senate
had not given its advice and consent to ratification of a CTBT.
07/23/96 — The United States and Russia announced their joint support for the
existing draft CTBT. While this draft did not fully satisfy either nation,
they viewed it as acceptable and the only route to achieving a CTBT in
07/29/96 — China conducted what it said would be its last nuclear test, and pledged
to begin a moratorium on testing on July 30.
08/07/96 — China and the United States reportedly reached an agreement on
modifying the draft treaty so as to resolve China’s concerns over CTBT
verification, clearing the way for China to support the treaty.
08/20/96 — India vetoed the draft CTBT in the CD, barring the treaty from going to
the U.N. General Assembly as a CD document.
08/23/96 — Australia asked the U.N. General Assembly to begin consideration of the
draft CTBT on September 9.
09/10/96 — The U.N. General Assembly adopted, 158 to 3 (with 5 abstentions and 19
nations not voting), the draft CTBT negotiated at the CD.
09/24/96 — The CTBT was opened for signing; President Clinton and others signed
11/20/96 — The Preparatory Commission for the Comprehensive Test Ban Treaty
Organization began its first meeting.
07/02/97 — The Department of Energy conducted its first subcritical experiment,
“Rebound,” at the Nevada Test Site. It conducted one more in 1997.
08/28/97 — The Washington Times reported Administration officials as saying Russia
may have conducted a nuclear explosion on August 16.
09/22/97 — President Clinton submitted the CTBT to the Senate for its advice and
consent to ratification.
11/04/97 — The Washington Post reported that the Administration formally dropped
its claim that a seismic event of August 16, 1997, was a Russian nuclear
01/21/98 — Senator Jesse Helms, in a letter to President Clinton, stated that “the
CTBT is very low on the [Senate Foreign Relations] Committee’s list of
01/27/98 — In his State of the Union address, President Clinton asked the Senate to
approve the CTBT this year and announced that four former Chairmen of
the Joint Chiefs of Staff had endorsed the treaty.
03/25/98 — The Department of Energy conducted its third subcritical experiment,
“Stagecoach,” at the Nevada Test Site. It conducted two more in 1998.
04/06/98 — Britain and France became the first declared nuclear weapon states to
ratify the CTBT, depositing instruments of ratification with the United
05/11/98 — Prime Minister Vajpayee announced India conducted three nuclear tests.
05/13/98 — India announced that it conducted two nuclear tests.
05/28/98 — Pakistan announced that it conducted five nuclear tests.
05/30/98 — Pakistan announced that it conducted one nuclear test.
The foreign ministers of China, France, Russia, the United Kingdom, and
the United States, in a joint communique, condemned the Indian and
Pakistani nuclear tests, urged India and Pakistan to refrain from
weaponizing or deploying nuclear weapons, and called on them to adhere
to the CTBT “immediately and unconditionally.”
Pakistan’s Prime Minister, Nawaz Sharif, in an address to the U.N., said
his nation would adhere to the CTBT if other nations lifted economic
sanctions, as long as India refrained from testing.
Secretary of Energy Bill Richardson and Secretary of Defense William
Cohen submitted the third annual nuclear stockpile certification
memorandum to the President stating, “The nuclear stockpile has no safety
or reliability concerns that require underground testing at this time.”
The Department of Energy conducted its sixth subcritical experiment,
“Clarinet,” at the Nevada Test Site. It conducted two more in 1999.
The Cox Committee, in its report, stated its belief that China may be
continuing to conduct underground nuclear tests.
In separate press conferences, President Clinton and nine Senators urged
the Senate to consider the CTBT. A new survey found 82% of Americans
want the treaty approved. All 45 Democratic Senators wrote to Senator
Helms urging him to hold hearings on the treaty and to report it to the
Responding to the July 20 letter, Senator Helms stated that “I do not share
your enthusiasm for this treaty” and that the Senate Foreign Relations
Committee would consider it after amendments to the ABM Treaty and
the Kyoto Protocol.
Senator Lott proposed a unanimous-consent request that would bring the
CTBT to the Senate floor for ten hours of debate beginning October 6, and
then to a vote.
(1) States that had ratified the CTBT ended a three-day conference on
expediting entry into force. (2) The Senate began debate on the treaty.
President Clinton wrote to Senators Lott and Daschle to request that a vote
on the CTBT be delayed.
The Senate rejected the CTBT on a vote of 48 for, 51 against, and 1
Secretary of State Albright announced that Gen. John Shalikashvili (ret.)
would head the Administration’s effort to achieve bipartisan support for
CTBT ratification, but the State Department indicated that the
Administration did not expect to seek Senate approval of the treaty in
DOE conducted the ninth U.S. subcritical experiment, “Oboe 3.” It held
four more in 2000.
Russia announced that it conducted seven subcritical experiments between
September 23, 1999, and January 8, 2000.
Russia ratified the CTBT.
Russia announced that it completed its fifth and final series of subcritical
experiments for 2000 at Novaya Zemlya during the week of October 30.
Colin Powell, as nominee for Secretary of State, said the Administration
would not ask for CTBT ratification in this session of Congress.
The New York Times reported U.S. intelligence experts were divided on
whether Russia had conducted clandestine tests over the past several
The House Appropriations Committee declined to add funds to the
FY2002 Energy and Water Development Appropriations Bill to increase
nuclear test readiness, arguing the Secretary of Defense, President, Armed
Services Committees, and Congress must first request or approve these
The National Nuclear Security Agency (NNSA) held the 14th U.S.
subcritical experiment, “Oboe 8.” It conducted one more in 2001.
The Conference on Facilitating the Entry into Force of the CTBT began
on this date at U.N. headquarters in New York and ended November 13.
NNSA held the 16th U.S. subcritical experiment, and the first with U.K.
participation, “Vito.” It conducted three more subcritical experiments,
without U.K. participation, in 2002.
The House passed H.R. 4546, as amended, the Bob Stump National
Defense Authorization Act for FY2003; it called for DOE to achieve the
ability to conduct a nuclear test within a year of a presidential direction to
The National Academy of Sciences issued a report asserting that the main
technical concerns raised in regard to the CTBT are manageable.
NNSA held the 19th U.S. subcritical experiment, “Rocco.”
A House Policy Committee report recommended “a test readiness program
that could achieve an underground diagnostic [nuclear] test within 18
months”; the Bipartisan Congressional Task Force on Nonproliferation
urged President Bush “not to resume nuclear weapons testing.”
The Senate passed, 98-1, S. 1050, the FY2004 National Defense
Authorization Bill. Sec. 3132 directed the Secretary of Energy to achieve
by October 1, 2006, and to maintain thereafter, the ability to conduct a
nuclear test within 18 months of a decision to test, unless the Secretary
determines that a different number of months is preferable.
A conference on facilitating the CTBT’s entry into force was held in
Vienna, Austria, September 3-5.
NNSA held the 20th U.S. subcritical experiment, “Piano.”
The First Committee (Disarmament and International Security) of the
U.N. General Assembly approved a draft resolution, “A Path to Total
Elimination of Nuclear Weapons,” 146-2, with 16 abstentions. A
provision of the draft resolution stressed the importance of achieving the
early entry into force of the CTBT. The United States and India voted no;
the U.S. representative stated that he did so because of U.S. opposition to
the CTBT. (See also 12/08/03.)
The 21st meeting of the CTBTO Preparatory Commission was held
November 10-13 in Vienna, Austria.
The U.N. General Assembly adopted, 164-2, with 2 abstentions, a
resolution, “A Path to Total Elimination of Nuclear Weapons.”
Libya became the 109th nation to ratify the CTBT.
NNSA held the 21st U.S. subcritical experiment, “Armando.”
In a joint statement, India and Pakistan agreed to reaffirm their unilateral
moratoria on nuclear testing, barring extraordinary events, and to establish
a dedicated and secure hotline between the two foreign secretaries.
The 22nd meeting of the CTBTO Preparatory Commission was held June
22-24 in Vienna, Austria.
Foreign ministers from 42 nations issue a statement calling entry into
force of the CTBT “more urgent today than ever before.”
The United Republic of Tanzania became the 119th nation to ratify the
CTBT and the 173rd to sign it.
The U.N. General Assembly adopted, 177-2, with 4 abstentions, a
resolution, “Comprehensive Nuclear-Test-Ban Treaty.”
The European Parliament passed a resolution that, among other things,
“reiterates its call for the USA ... to sign and ratify the CTBT.”
At the Nuclear Nonproliferation Treaty Review Conference, held May 2
to 27, some nations criticized the United States for not ratifying the
The New York Times reported that on May 15, National Security Advisor
Stephen Hadley stated, “Action would have to be taken” if North Korea
conducted a nuclear test, and that Secretary General Shinzo Abe of
Japan’s Liberal Democratic Party said if North Korea “conducts nuclear
testing, for instance, Japan will naturally bring the issue to the U.N. and
call for sanctions against North Korea.”
Egyptian Foreign Minister Ahmed Aboul Gheit reportedly stated that
Egypt would not ratify the CTBT until Israel joins the NPT.
A conference, Facilitating the Entry into Force of the Comprehensive
Nuclear Test Ban Treaty, is scheduled for September 21 to 23 at U.N.