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 failures to agree 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 that the JCPOA was terminated on 18 October 2025 (ten years after its start date).
While the IAEA had carried out about a dozen inspections in Iran since the war with Israel and the bombings by the US in June 2025, it had not been given access to the most important nuclear facilities: Fordow, Natanz and Isfahan, each of which was bombed by the US. Although Iran and the IAEA reached an agreement in Cairo in September 2025, establishing procedures for resuming inspections consistent with the Safeguards Agreement, Iran did not provide a report on the status of nuclear material and facilities, as required. Inspectors from the IAEA visited other nuclear sites in Iran, including the Tehran Research Reactor, on 10 November 2025, but on 20 November 2025, the IAEA Board of Governors adopted a resolution calling on Iran to provide the IAEA with information on the status of its uranium stockpile and nuclear facilities “without delay” and to grant it all access required to verify this information. The resolution amended the IAEA’s reporting mandate to include reporting on the provisions of “all relevant” UN Security Council resolutions, including those reimposed through the snap-back procedure. Iran formally withdrew from the Cairo agreement on the same day.
On 26 January 2026, the IAEA issued a statement that it could not conclude that there had been no diversion of nuclear material for non-peaceful purposes, and Iran responded on 2 February 2026 that it could not facilitate further inspections due to continued aggression and threats that had made them “legally untenable” and “materially impractical.” On 6 February 2026, the IAEA reported that commercial satellite imagery suggested construction work underway at the bombed Isfahan facility and requested access. Iran refused, reiterating its 2 February 2026 response about their being impractical. The IAEA remained actively involved with the issue and its Director-General Grossi was reportedly “in attendance.” during indirect bilateral US-Iran talks in Geneva on 22 and 25 February 2026.
The US and Israel launched extensive military strikes on Iran on 28 February, which included some nuclear facilities (Natanz, Bushehr, and the Khondab heavy water plant). Among the numerous arguments mentioned to justify the attacks, was the continuation of Iran’s nuclear program. The IAEA confirmed damage to the nuclear facilities from a review of commercial satellite imagery, and Iran granted it limited access to its Bushehr site on 1-3 June 2026.
The IAEA Director-General’s report on 4 June 2026 stated that the IAEA could not verify whether Iran has suspended all enrichment-related activities, including research and development, whether Iran has suspended all reprocessing activities, the size of Iran’s uranium stockpile, whether Iran has suspended work on all heavy water-related projects, and Iran’s inventories of centrifuges and related equipment.
On 17 June 2026, the US and Iran agreed to a 14-point Memorandum of Understanding, mediated by Pakistan, to halt hostilities, ease maritime constraints, and open a 60-day window for a permanent peace deal between the two countries. After Iran launched military attacks on commercial shipping vessels in the Strait of Hormuz, US President Trump declared the deal over on 8 July 2026, and the US resumed attacks on Iran. Sporadic attacks by US forces and Iranian attacks on vessels navigating the Strait of Hormuz have effectively closed the strait for normal commercial activities. The war continues, and the situation remains stalemated.
Although the Iran sanctions regime was re-introduced on the UN’s website in September 2025, disagreements about the reimposition of the snap-back provisions have prevented the reestablishment of both the Sanctions Committee and the Panel of Experts, rendering the regime effectively inoperable at the UN level. The ambiguous status of the Iran sanctions regime has also prevented Security Council agreement on the appointment of new Committee chairs for the other sanctions regimes, forcing the Council to conduct Committee activities through the rotating presidency of the Council each month.
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 not re-established. 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 faltered 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 status 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. The ongoing military conflict between the US and Iran is more important than the reimposition of sanctions.
Constraint
Policy outcome
Iran had built up stocks of highly enriched uranium and moved much of it prior to the 2025 airstrikes on its core production facilities. Renewed UN sanctions could contribute to additional constraint, although the US, EU, and UK had already imposed unilateral sanctions on individuals and sectors that had been given 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 and the additional military attacks in 2026 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 stigmatized by being once again 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/or criminality, strengthening of authoritarian rule, rally round the flag effect, harmful effects on neighboring states, strengthening of political factions, enhancing stature of targeted individuals, increase in international regulatory capacity in different issue domains, increase in international enforcement capacity in different issue domains, increase in the growth of the state role in the economy, significant burden on implementing states, humanitarian consequences, decline in the credibility and/or legitimacy of UN Security Council.
