The United States says it is ready to talk to Iran about both nations returning to a 2015 agreement that aimed to prevent Tehran acquiring nuclear weapons, seeking to revive a deal that Washington abandoned nearly three years ago.
Iran reacted coolly to the US idea, which was conveyed by US Secretary of State Antony Blinken during a video meeting with his British, French and German counterparts gathered in Paris.
Blinken reiterated the US position that President Joe Biden's administration would return to the accord formally known as the Joint Comprehensive Plan of Action (JCPOA) if Iran came into full compliance with the deal.
"Secretary Blinken reiterated that ... if Iran comes back into strict compliance with its commitments under the JCPOA, the United States will do the same and is prepared to engage in discussions with Iran toward that end," a joint statement from the four nations said on Thursday.
A US official told Reuters that Washington would respond positively to any European Union invitation to talks among Iran and the six major powers who negotiated the original agreement: Britain, China, France, Germany, Russia and the United States.
"We are ready to show up if such a meeting were to take place," the official told Reuters, speaking on condition of anonymity, after a senior EU official said he was prepared to convene such a meeting among the parties to the deal.
London, Paris and Berlin welcomed Biden's intention to return to diplomacy with Iran. But Iranian Foreign Minister Mohammad Javad Zarif fired back that it was for Washington to make the first move.
Iran began breaching the deal in 2019 after former president Donald Trump withdrew the United States from the deal and reimposed economic sanctions.
Tehran has accelerated its breaches in recent months and become locked in a stand-off with Biden's administration over who should move first to save the accord.
"Instead of sophistry & putting onus on Iran, E3/EU must abide by own commitments & demand an end to Trump's legacy of #EconomicTerrorism against Iran," Zarif said in a tweet.