Iran has begun the process of producing enriched uranium metal, it has told the global nuclear watchdog.
Tehran informed the International Atomic Energy Agency (IAEA) that the process was to develop fuel for a research reactor.
But uranium metal could also be used to make the core of a nuclear bomb.
European powers said Iran’s move breached a nuclear deal and threatened talks to revive it. The US called it an “unfortunate step backwards”.
The 2015 deal, known formally as the Joint Comprehensive Plan of Action (JCPOA), saw Iran agree to restrictions its nuclear programme that were designed to minimise the risk of it developing a nuclear weapon.
In return, six world powers – China, France, Germany, Russia, the US and the UK – agreed to lift economic sanctions that were in place.https://emp.bbc.com/emp/SMPj/2.43.6/iframe.htmlmedia captionIran’s nuclear programme: What’s been happening at its key nuclear sites?
Former US President Donald Trump pulled the US out of the deal in 2018 and reinstated sanctions on Iran. Iran retaliated by gradually breaching its commitments under the accord.
Mr Trump’s successor, Joe Biden, has said he will rejoin the deal and lift sanctions if Iran returns to full compliance, but Iran wants him to make the first move.
Representatives of Iran and the five world powers still party to the deal have been attempting to agree a compromise at talks in Vienna, with US envoys participating indirectly.
The talks began in April and the latest round was adjourned on 20 June, with no date set for the next meeting.
In a statement on Tuesday, the IAEA said: “Today, Iran informed the agency that UO2 [uranium dioxide] enriched up to 20% U-235 would be shipped to the R&D [research and development] laboratory at the Fuel Fabrication Plant in Esfahan, where it would be converted to UF4 [uranium tetrafluoride] and then to uranium metal enriched to 20% U-235, before using it to manufacture the fuel.”
The British, French and German foreign ministers said that they had “grave concerns” about Iran’s decision.
“Iran has no credible civilian need for uranium metal R&D and production, which are a key step in the development of a nuclear weapon,” the ministers said in a joint statement.
“With its latest steps, Iran is threatening a successful outcome to the Vienna talks despite the progress achieved in six rounds of negotiations.”
The statement also urged Iran to return to the talks in the Austrian capital.
US state department spokesperson Ned Price said that although they were not setting a deadline for the talks, “as time proceeds Iran’s nuclear advances will have a bearing on our view of returning to the JCPOA”
