Summary
On 27 September 2025, nearly ten years after the passage of UNSCR 2231 (which incorporated and endorsed the JCPOA), all of the UN Security Council sanctions previously applied to Iran (contained in UNSCRs 1696, 1737, 1747, 1803, 1835 and 1929, dating from 2006 to 2010) were reinstated due to the triggering of the snapback mechanism by the E3 signatories of the agreement (the UK, France, and Germany). The activation of the snapback mechanism followed the failures to extend the JCPOA for another six months proposed by China and Russia on 19 and 26 September 2025.
Although Iran, Russia and China argued that the “snapback” notification was “null and void,” the Iran sanctions regime was returned to the UN sanctions architecture under the heading of the “1737 Sanctions Committee.” This technically restored the Iran Sanctions Committee and Panel of Experts, but there was no action on either during Russia’s Presidency of the Council in October 2025. According to the International Crisis Group, Russia’s UN envoy asserted on 1 October 2025 that “We’ll be living in two parallel realities, because for some snapback happened, for us it didn’t,” contending later in the month that the JCPOA was terminated on 18 October 2025.
While the IAEA had carried out about a dozen inspections in Iran since the war with Israel in June 2025, it had not been given access to the most important nuclear facilities: Fordow, Natanz and Isfahan, which were bombed by the US. Inspectors from the IAEA visited other nuclear sites in Iran, including the Tehran Research Reactor, in November 2025, and China encouraged a resumption of talks.
Purposes
Coerce
Coerce Iran to suspend its nuclear activities, including enrichment, and comply with IAEA requirements.
Constrain
Constrain Iran’s access to sensitive technologies in support of its nuclear and missile programs.
Signal
Signal to Iran the costs of non-compliance and signal continued support for non-proliferation norms.
Sanctions type
Mandatory
Newly reimposed sanctions:
- Individual/entity asset freeze;
- Travel ban;
- Arms exports embargo;
- Arms imports embargo (on specific weapons);
- Proliferation sensitive goods and technology imports and exports ban (specific items and the related transfer, training, assistance, investment, brokering, and other services, including nuclear weapon delivery systems restrictions);
- Investment ban (prohibition on Iran acquiring interest in any commercial activity involving uranium mining or production or use of nuclear material and technology).
Conditional
Newly reimposed conditional restrictions:
- Bunkering ban (if reasonable grounds for sanctions violation).
Exemptions
Designations
Current and maximum number of designees during the episode: 43 individuals and 78 entities.
Current list of sanctions designees:
https://main.un.org/securitycouncil/en/sanctions/1737/materials
Potential scope
Potential scope of impact
UN sanctions can have some non-discriminating impact on the general population, since they include arms embargoes, diplomatic sanctions, and/or restrictions on the conduct of particular activities or the export of specific commodities.
Implementation
Previously terminated Sanctions Committee and Panel of Experts re-authorized, but Panel of Experts not formed. Designation criteria were specified and targets designated. Enforcement authorities specified (IAEA has enforcement role).
Implementation assistance notices:
- Financial and business measures
- Conventional arms and related materiel
- Specific vessels (M/V Hansa India, M/V Monchegorsk)
Panel of Experts reports (2012-2015):
https://main.un.org/securitycouncil/en/sanctions/1737/panel-of-experts/reports
Security Council facilitator reports (2016-2025):
https://www.un.org/securitycouncil/content/2231/reports-and-briefings-facilitator
Effectiveness
Coercion
Policy outcome
Nuclear negotiations stalled since the reimposition of UN sanctions via the UNSCR 2231 (2025) “snapback” mechanism at the start of the episode, and IAEA inspections remain severely curtailed. resulting in a limited view of the current state of Iran’s nuclear program.
Sanctions contribution
Most G7+ countries have reimposed UN sanctions, but the outlook for other UN Member States is uncertain, given the non-recognition of snapback by Iran, Russia, and China.
Constraint
Policy outcome
Iran had built up stocks of highly enriched uranium and moved much of it prior to the airstrikes on its core production facilities. Renewed UN sanctions are likely to contribute to additional constraint, although the US, EU, and UK had imposed unilateral sanctions on individuals and sectors that had experienced sanctions relief under the JCPOA, in previous years.
Sanctions contribution
Unclear given ambiguities about global implementation of the renewed UN sanctions measures. Israeli and US bombing attacks in June 2025 were more significant to current levels of constraint experienced by Iran.
Signaling
Policy outcome
Non-proliferation norms have been rearticulated by the activation of the snapback mechanism, but the opposition of Russia and China, combined with the uncertainty about the response of the global community, raise questions about the sustainability of the signal.
Sanctions contribution
Snapback was a significant development and Iran is once more included in the UN’s sanctions architecture, contributing to broader signaling with respect to Iran and non-proliferation norms.
Overall
Unintended consequences
Increase in corruption and criminality, harmful effects on neighboring states, increase in international regulatory and enforcement capacity in different issue domains, humanitarian consequences, decline in the credibility and/or legitimacy of UN Security Council, widespread harmful economic consequences.
