Iran retaliated by violating the limits imposed under the accord on its nuclear programme. It now seeks an end to United States sanctions.
Under JCPOA, Iran limited its nuclear program to make it harder to obtain fissile material for atomic weapons in return for relief from US, EU and UN sanctions.
The goal is to find a way back to the accord known by its acronym JCPOA, which former US president Donald Trump walked away from and which his successor Joe Biden wants to revive.
The goal is to find a way back to the accord known by its acronym JCPOA, which former US president Donald Trump walked away from and which his successor Joe Biden wants to revive.
Iranian Supreme Leader Ayatollah Ali Khamenei called remarks by the country's foreign minister as a "big mistake", a week after audio emerged of the minister criticised the military's influence on diplomacy.
President Rouhani, who is approaching the end of his second and final term, stated that the audio leak was timed to sow discord in Iran, just as the Vienna talks were "at the height of their success".
Envoys from China and Russia to the Iran nuclear talks said on Friday there had been progress in efforts to bring Iran and the United States back into compliance with the 2015 nuclear deal and that all sides would reconvene next week.
Neither the United States nor Iran expect fast breakthroughs in the talks that began in Vienna on Tuesday, with European and other diplomats acting as intermediaries because Iran rejects face-to-face talks for now.
On Wednesday, diplomats from major powers met separately with leaders from Iran and the United States, to discuss how to bring both countries back into the fold of the nuclear deal, which was abandoned three years ago.
The United States is prepared to remove sanctions on Iran to resume compliance with the Iran nuclear deal, including those that are inconsistent with the 2015 pact.
Earlier this month, Iranian supreme leader Ayatollah Ali Khamenei said his country may return to full compliance of the JCPOA if Tehran deems Washington has honoured its commitments.
The stockpile of "enriched uranium will increase", he said, stressing that Tehran has the right within the deal to stop observing commitments "totally or partially" if the other parties fail to honour theirs.
"There's a lot of work to be done," but "I don't expect an immediate solution," Guterres said during a press conference when asked about the possibility of mediating a way out of the impasse.