Iran needs stronger guarantees from Washington for the revival of the 2015 nuclear deal, its foreign minister said, adding that the UN atomic watchdog should stop its “politically motivated investigations”. about Tehran’s nuclear work.

After 16 months of indirect talks between Tehran and Washington, EU foreign policy chief Josep Borrell said on August 8 that the bloc had submitted a final offer to break the deadlock and revive the deal.

Top Iranian diplomat Hossein Amirabdollahian said Wednesday that Tehran was carefully reviewing Washington’s response to the text, which was forwarded last week by the EU in its role as coordinator of the talks.

“Iran is carefully reviewing the text drafted by the EU… We need stronger guarantees from the other side to achieve a sustainable agreement,” Amirabdollahian told a joint news conference with his Russian counterpart in Moscow.

Amirabdollahian did not elaborate on the “strongest guarantees”, but during months of talks with Washington in Vienna, Tehran demanded assurances from the United States that no future US president would abandon the deal, as Donald Trump did in 2018.

President Joe Biden cannot give those ironclad guarantees because the agreement is a political understanding and not a legally binding treaty.

White House national security spokesman John Kirby said he had not seen the Iranian foreign minister’s comments.

“So I don’t know what guarantees you’re talking about,” Kirby told reporters. The United States is waiting for a response from the EU and the Iranians.

“Although we are, as I have said before, cautiously optimistic, we are also pragmatic and realize that there are still gaps, and we are trying to close those gaps in good faith, negotiating through the proper channels and not through the public.” Kirby added.

Meanwhile, Iran has begun enriching uranium with the second of three cascades, or clusters, of advanced IR-6 centrifuges recently installed at an underground plant in Natanz, according to a report by the UN nuclear watchdog seen by Reuters.

Like the first of those three cascades of up to 174 machines each, the second is enriching uranium to 5% fissile purity and the third has not been fueled with nuclear material, the confidential report to member states said.