The United States and European powers have warned Iran that its latest uranium enrichment efforts could imperil talks taking place in Vienna on reviving the Iran nuclear deal.
The warnings came hours after the International Atomic Energy Agency (IAEA) reported that Iran intended to enrich uranium to 20 percent -- a move that takes it a step closer to developing materials that could be used to make a nuclear weapon.
Washington called on Tehran to halt its "brinksmanship" and return to Vienna prepared for real talks “in a position to be prepared to finish the work,” State Department spokesman Ned Price said.
"It is worrying that Iran is choosing to continue to escalate its nonperformance of its JCPOA commitments, especially with experiments that have value for nuclear weapons research," Price said, referring to the deal, known as the Joint Comprehensive Plan of Action. "It's another unfortunate step backwards for Iran."
The foreign ministers of Britain, France, and Germany also spoke out, expressing "grave concern" and warning that Iran's move endangers the discussions.
"With its latest steps, Iran is threatening a successful outcome to the Vienna talks despite the progress achieved in six rounds of negotiations to date," the ministers said in a statement.
Iran should return to the negotiations "without delay" and aim to bring them to a swift conclusion, they warned. "We have repeatedly stressed that time is on no one's side."
The EU ministers said Iran’s move “is all the more concerning at a time when no date has been set for the continuation of the negotiations in Vienna on a return to the JCPOA."
Britain, France, Germany and the United States are among the global powers, along with China and Russia, that negotiated the deal with Iran aimed at restricting its nuclear program.
An IAEA statement on July 6 said Tehran had told the agency that it would be sending the enriched uranium to its research and development laboratory at the fuel production plant in Isfahan.
The aim would be to make fuel for a research reactor, the agency added.
The three European ministers called it a "serious violation" of Iran's commitments under the 2015 nuclear deal.
"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," they added.
Former U.S. President Donald Trump pulled the United States out of the deal in 2018. President Joe Biden has expressed readiness to rejoin the deal if conditions are met by Iran.