• The E3—France, Germany, and the UK—are preparing to initiate the UN snapback mechanism to reimpose broad sanctions on Iran.
  • The move follows failed diplomatic talks and Iran's refusal to meet key demands on nuclear monitoring and uranium enrichment.
  • Reinstated sanctions would include a conventional arms embargo, ballistic missile restrictions, and asset freezes, with significant economic ramifications.

European powers are finalizing plans to trigger a United Nations process to reimpose sweeping international sanctions on Iran as early as Thursday, according to people familiar with the matter. The move by France, Germany, and the United Kingdom—collectively known as the E3—comes after recent negotiations in Geneva ended without a resolution and Iran declined a last-ditch offer for a six-month extension.

The snapback mechanism, a provision within the 2015 Joint Comprehensive Plan of Action (JCPOA), would automatically reinstate the full panoply of UN sanctions that were in place before the nuclear deal. This includes a conventional arms embargo, restrictions on ballistic missile development, asset freezes, travel bans, and prohibitions on nuclear-related technology.

Diplomatic efforts to avert this outcome have faltered. The E3 had offered to delay the snapback process if Tehran agreed to restore full monitoring access for the International Atomic Energy Agency (IAEA), clarify its stockpile of enriched uranium, and resume negotiations with the U.S. Iranian officials have thus far rejected these terms, arguing that the European powers forfeited their legal standing to trigger snapback by failing to deliver the JCPOA's promised economic benefits after the U.S. withdrew from the pact in 2018.

The escalating tension follows a period of heightened nuclear activity by Iran, which enriched uranium to near weapons-grade levels earlier this year, and a direct military confrontation with Israel in June that included attacks on Iranian nuclear facilities. Since then, Tehran has further reduced its cooperation with international inspectors.

A formal filing at the UN Security Council would set a 30-day clock for the automatic reinstatement of sanctions, a process that cannot be vetoed. The move signals a profound deterioration in EU-Iran relations and is expected to have immediate consequences for the Iranian economy, likely restricting its oil exports and cutting off access to the international financial system. Attempts to reach spokespeople for the French and German foreign ministries for immediate comment were not immediately successful.