EU foreign policy chief Josep Borrell is pressing the US to respond to the proposal to complete the Vienna talks on Iran's nuclear deal.
Borell also said that he had received “amendments” from Iran despite its approval of the proposed draft.
Meanwhile, senior US officials confirmed that Iran had waived some of the basic conditions for reviving the 2015 agreement.
Both the EU and Iran are awaiting a response from the Biden administration regarding the Iranian package of amendments to the final draft proposal, which came after intermittent and indirect talks between Washington and Tehran over 16 months.
Despite the EU wanting to bring talks to fruition, a US official told Reuters that gaps remain between the US and Iran and that “it could take a little longer” to come to a final agreement, if one is possible.
“We’re studying Iran’s response now and we'll get back to them soon,” the official said.
Earlier, State Department spokesman Ned Price said there was no guarantee a deal can be struck, saying “the outcome of these ongoing discussions still remains uncertain as gaps do remain.”
This came at a time when Borrell sought to pressure the Biden administration to respond to the EU proposal.
Most countries involved in nuclear talks with Iran agree with the EU proposal that aims to save the deal, he said on Tuesday.
“Most of them agree, but I still don't have the answer from the United States, who I understand have to discuss it, and we expect during this week to receive an answer,” Borrell said in an interview with Spain's national broadcaster TVE.
He had said on Monday he considered Tehran's answer “reasonable.”
Iran had criticized the EU and Washington for they delayed response to its proposal.
“The Americans are procrastinating, and there is inaction on the European side... America and Europe need to reach an agreement more than Iran,” Iranian Foreign Ministry Spokesman Nasser Kanaani had said in a Monday presser.
Price denied that the US had any role in obstructing negotiations in any way.