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U.N. Ban on Iran Arms Transfers
Overview
agreed to the sale to Iran of the S-300 air defense system,
Annex B of U.N. Security Council Resolution 2231 (July
with a reported estimated value of about $800 million. The
17, 2015), which enshrined the multilateral Iran nuclear
two governments reportedly disagreed later over payment
agreement (Joint Comprehensive Plan of Action, JCPOA),
and other terms, and Russia did not deliver it until
provides for a ban on arms transfers to or from Iran until
November 2016. A State Department spokesperson said in
October 18, 2020. Major arms suppliers have apparently not
May 2016 that “[w]hile we’re opposed to the sale, it is not
violated the restriction by transferring major combat
formally a violation [of 2231]” because the S-300 is for
systems to Iran, but U.S. and U.N. officials and reports state
defensive uses only.
that Iran has not abided by the ban on exporting arms. The
Trump Administration and many in Congress advocate an
Figure 1. Iran’s Regional Allies
extension of the U.N. arms transfer ban, but two key
potential arms suppliers of Iran—Russia and China—are
veto-wielding members of the Security Council and support
the expiration of the ban.
Annex B also contains a ban, until October 18, 2023, on
supplying equipment that Iran could use to develop nuclear-
capable ballistic missiles, and it calls for Iran not to develop
ballistic missiles designed to carry a nuclear weapon. These
missile-related provisions are addressed separately in CRS
Report RS20871, Iran Sanctions, by Kenneth Katzman.
Provisions of the Arms Transfer Ban
Annex B of Resolution 2231 continued similar restrictions
in previous U.N. Security Council resolutions on Iran.
Resolution 1747 (March 24, 2007) contained a ban on
Iran’s transfer o
f arms from its territory and required all
Source: Defense Intel igence Agency. Iran Military Power: 2019.
U.N. member states to prohibit the transfer of Iranian arms
to their nationals. Resolution 1929 (June 9, 2010) contained
Effects of the Ban
a ban (Resolution 1747 had a voluntary restriction) on the
supply to Iran of “any battle tanks, armoured combat
The U.S. government assesses that the ban on selling arms
to Iran apparently has been effective. According to
vehicles, large calibre artillery systems, combat aircraft,
Appendix J o f the congressionally mandated Defense
attack helicopters, warships, missiles or missile systems as
Intelligence Agency (DIA) annual report on the military
defined for the purpose of the United Nations Register of
Arms or related materiel, including spare parts…
power of Iran for 2019, released in November 2019, Iran
.” These
has not obtained any major combat systems from foreign
restrictions are restated in Annex B of Resolution 2231,
suppliers since the ban went into effect. It states that Iran
which supersedes all previous Security Council resolutions
wants to “purchase new advanced weapon systems from
on Iran. Annex B permits the importation and exportation
foreign suppliers to modernize its armed forces, including
of such arms by Iran if the U.N. Security Council provides
advance approval on a “case
equipment it has largely been unable to acquire for
-by-case basis.” Such approval
decades.” The report adds that once the U.N. ban on arms
is virtually impossible; officials in both the Obama and
sales to Iran expires, Iran “will be permitted to purchase
Trump Administrations have consistently said they could
conventional systems it is unable to produce domestically,
not envision U.S. approval of arms transfers to or from Iran.
such as advanced fighter aircraft and main battle tanks. Iran
is already evaluating and discussing military hardware for
The Iran arms transfer ban in Resolution 2231 applies “until
purchase primarily from Russia and, to a lesser extent,
the date that is five years after the JCPOA Adoption Day”
China.” According to the report, “Iran’s potential
(Adoption Day was October 18, 2015, 90 days after the
acquisitions after the lifting of UNSCR 2231 restrictions
passage of Resolution 2231). The restriction would expire
include Russian Su-30 fighters, Yak-130 trainers, and T-90
earlier if the International Atomic Energy Agency (IAEA)
MBTs (main battle tanks). Iran has also shown interest in
were to issue a “Broader Conclusion” that all nuclear
acquiring S-400 air defense systems and Bastian coastal
material in Iran remains in peaceful activities.
defense systems from Russia.” For information on the
composition of Iran’s forces, see Figure 2.
U.S. and other Security Council member officials widely
interpret the restriction as inapplicable to the sale to Iran of
systems for purely defensive purposes. In 2007, Russia
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U.N. Ban on Iran Arms Transfers
Figure 2. Iran Military Structure and Size Estimates
indefinitely. However, even if U.S. allies support the U.S.
position, officials of Russia and China, whose governments
seek to sell significant packages of new major combat
systems to Iran, have stated that they will reject any attempt
to extend the arms transfer ban.
On April 29, Secretary of State Michael Pompeo stated to
journalists: “We’re not going to let [Iran’s purchase of
conventional arms] happen. We will work with the U.N.
Security Council to extend that prohibition on those arms
sales and then in the event we can’t get anyone else to act,
the United States is evaluating every possibility about how
we might do that.” The statement appeared to confirm press
reports about Administration strategy to try to compel other
Security Council members to enact an extension of the ban.
Source: Defense Intel igence Agency. Iran Military Power: 2019
According to an April 27, 2020, New York Times report,
By contrast, the ban on Iranian arms exports has arguably
this strategy includes a threat to trigger a provision of
not been effective. According to the DIA report, which
Security Council Resolution 2231 that would reimpose the
represents a consensus U.S. judgment, “Since the Islamic
sanctions suspended by that Resolution. This option is
Revolution, Iran has transferred a wide range of weapons
available, according to the report, because the State
and military equipment to state and non-state actors,
Department has found that the United States can assert that
including designated terrorist organizations.… Although
it remains a “participant” in the JCPOA, according to the
some Iranian shipments have been interdicted, Tehran is
Resolution 2231 definition. Under the reported reasoning,
often able to get high-priority arms transfers to its
the Trump Administration’s withdrawal from the accord did
customers. [See Figure 1]. Over the years, Iranian transfers
not changes its status as a “participant” for U.N. purposes.
to state and non-state actors have included communications
Resolution 2231 stipulates that a JCPOA participant could,
equipment; small arms —such as assault rifles, sniper rifles,
after notifying the Security Council of an issue that the
machine guns, mortars, and rocket-propelled grenades
government “believes constitutes significant non-
(RPGs)—and ammunition; … artillery systems, including
performance of [JCPOA] commitments,” trigger an
MRLs (multiple rocket launchers) and battlefield rockets
automatic draft resolution keeping sanctions relief in effect.
and launchers; armored vehicles; FAC (fast attack craft);
A U.S. veto of this resolution would reimpose the
equipment for unmanned explosives boats; … SAMs
suspended sanctions.
(surface-to-air missiles); UAVs (unmanned aerial vehicles)
… ground-attack aircraft …” and other weaponry. See CRS
European, Iranian, Russian, and other officials reacted to
Report R44017, Iran’s Foreign and Defense Policies, by
the New York Times report by stating that any U.S. attempt
Kenneth Katzman
to trigger a snapback of all sanctions through Resolution
2231 would not be viewed as legitimate. These
Relevant Laws, Authorities, and Options governments argue that the context of the snapback
for the Administration and Congress
provisions implies that only active JCPOA participants can
The stated policy of the Trump Administration is to apply
trigger the snapback mechanism, and the U.S. withdrawal
“maximum pressure” on Iran’s economy, through the
from the JCPOA denies the United States that ability.
imposition of U.S. sanctions, to compel Iran to alter its
behavior. One of the reasons the Administration gave for its
Were the United States to fail to achieve a U.S. extension of
exit from the JCPOA is that the nuclear restrictions in it, as
the ban, the Administration might decide to use its
well as the restrictions on arms transfers in Resolution
sanctions laws and authorities to deter any arms sales to
2231, are temporary. For almost a year, the Administration
Iran. These include the Iran-Iraq Arms Non-Proliferation
has been indicating that it insists on keeping the arms
Act, the Iran, North Korea, and Syria Nonproliferation Act
transfer ban in place. On October 18, 2019, in advance of a
(INKSNA), and Executive Order 13382. Additionally, the
meeting with Israel’s Prime Minister Binyamin Netanyahu,
Countering America’s Adversaries through Sanctions Act
held one year before the U.N. restriction is to expire,
authorizes sanctions for the sale to Iran of the combat
Secretary Pompeo stated that “The Security Council must
systems enumerated by Annex B. Iran’s designation as a
renew the arms embargo.” For their part, Iranian leaders
state sponsor of terrorism provides additional authorities for
have advocated for staying in the JCPOA in part to ensure
the President to sanction countries that supply arms to Iran.
the expiration of the ban—perhaps because, under the
For more detail on these provisions, see CRS Report
JCPOA, Iranian withdrawal could potentially trigger a
RS20871, Iran Sanctions, by Kenneth Katzman. Still, it is
“snapback” of all sanctions that were in place prior to the
not known from open sources whether the apparent restraint
agreement.
shown by such suppliers as Russia and China in proceeding
with new arms sales to Tehran are a result of the Annex B
In late April, press reports stated that the Administration
restriction, or the threat from U.S. secondary sanctions.
has begun circulating to its major European allies France,
the United Kingdom, and Germany, a draft Security
Kenneth Katzman, Specialist in Middle Eastern Affairs
Council resolution that would extend the arms transfer ban
IF11429
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U.N. Ban on Iran Arms Transfers
Disclaimer
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