France, Germany, the United Kingdom, and the European Union told US Secretary of State Marco Rubio they will trigger the UN snapback sanctions mechanism against Iran on Thursday, Axios reported, citing three sources with direct knowledge.
Reuters previously reported that the E3 were likely to begin the process this week, citing four diplomats familiar with the discussions.
The mechanism could lead to the reimposition of all United Nations Security Council sanctions that were lifted under the 2015 nuclear deal, depending on whether a diplomatic solution is reached in the coming weeks.
Diplomats cite Iran's failure to act
European officials told Axios the decision follows months of unproductive talks. The European powers, known as the E3, had warned Iran they would act by the end of August unless Tehran resumed nuclear negotiations with the US, restored access for UN inspectors and addressed concerns over its stockpile of highly enriched uranium.
A senior European diplomat said Iran had taken no clear steps to meet these demands and failed to offer detailed proposals during a meeting in Geneva this week. The diplomat said Iran was in "clear violation" of the nuclear agreement and left no room to extend the deadline.
Iran threatens to end inspector cooperation
Iranian Deputy Foreign Minister Kazem Gharibabadi said on Wednesday that if the Europeans activate snapback, Iran will retaliate, including by halting cooperation with the International Atomic Energy Agency.
Gharibabadi also argued the E3 no longer have the legal standing to invoke the snapback since, in Iran's view, they have not upheld their side of the 2015 deal. He warned that activating the mechanism would halt progress with UN inspectors, who recently re-entered Iran after months of restricted access.
UN sanctions to return unless deal is reached
Under Security Council Resolution 2231, which endorsed the 2015 agreement, any party can trigger snapback by filing a complaint of non-compliance. If the Security Council does not resolve the issue within 30 days, all prior UN sanctions could automatically return. These include arms embargoes, missile restrictions and inspections of Iranian cargo.
European officials said they hope to finalize the process before Russia assumes the rotating presidency of the Security Council in October. One diplomat told Axios that diplomacy remains possible in the next few weeks, despite the activation of snapback.
Nuclear program still monitored at Bushehr
Gharibabadi said IAEA inspectors were recently allowed to monitor Iran’s Bushehr power plant. He said their presence is necessary to avoid a shutdown, as the Russian-supplied reactor must be refueled in the presence of inspectors.
Foreign Minister Abbas Araghchi added that Iran will continue cooperation with the IAEA at Bushehr, though broader access could be restricted.
Diplomacy stalls
Since June, Iran and the European parties have held two rounds of talks — in Istanbul in July and Geneva on Tuesday — without announcing progress. Iran said the latest US sanctions on its shipping and aviation sectors prove Washington and Europe have failed to honor the deal.
Iran has also warned it could withdraw from the nuclear non-proliferation treaty if snapback proceeds. The process now moves into a 30-day window before sanctions could be restored.