The US on Thursday said it was ready to meet Iran and reversed former president Donald Trump's claims of new UN sanctions, providing an opening to restart nuclear diplomacy.
Hours after Secretary of State Antony Blinken spoke to his European counterparts, the US welcomed a proposal to convene talks between all nations that were part of the 2015 Iran nuclear deal.
The EU political director, Enrique Mora, afterwards proposed via Twitter an informal meeting of all participants, saying the nuclear accord was at a "critical moment" before a weekend deadline for Iran to restrict some UN nuclear inspections.
"The United States would accept an invitation from the European Union High Representative to attend a meeting of the P5+1 and Iran to discuss a diplomatic way forward on Iran's nuclear programme," State Department spokesman Ned Price said.
The group that sealed the 2015 deal includes the US and Iran as well as Britain, China, France, Germany and Russia.
Mr Trump withdrew from the nuclear accord and instead imposed sweeping sanctions aimed at bringing Iran to its knees.
But President Joe Biden supports a return to diplomacy, saying that the 2015 accord was effective in reducing Tehran's nuclear programme.
It remains to be seen if Iran will be willing to sit down with the US.
Iran insists that the US first lifts sanctions before it returns to full compliance with the 2015 accord, reversing steps it took in protest against Mr Trump's measures.
On Thursday, the Biden administration said it was no longer contending that the UN had imposed new sanctions on Iran.
In a letter, the acting US ambassador to the United Nations, Richard Mills, said that sanctions said to be reinstated in August "remain terminated".
Former secretary of state Mike Pompeo had argued that the US was still technically a participant in the 2015 accord and was triggering UN sanctions for breaches.
Even close US allies dismissed the argument and the UN said that no such additional sanctions had come into force.
