US National Security Adviser Jake Sullivan said on Friday that talks on the return by Iran and the United States to compliance with the 2015 Iran nuclear deal "are not going well".
"We do not yet have a path back into the JCPOA," Sullivan said in a webinar, as quoted by Reuters. He added that efforts to salvage the 2015 deal have "proven more difficult" this year than the US would have liked to see.
Sullivan also said the United States has conveyed through European negotiators to Iran its "alarm" over Tehran's "forward progress" in its nuclear program.
His comments came as the remaining parties to the 2015 Iran nuclear met in Vienna to adjourn the talks on salvaging the deal.
The European parties who took part in the talks said that "some technical progress" had been made but warned they were "rapidly reaching the end of the road".
"There has been some technical progress in the last 24 hours, but this only takes us back nearer to where the talks stood in June," Britain, France and Germany, known as E3, said in a statement after the latest round of discussions ended in Vienna, according to AFP.
"We are rapidly reaching the end of the road for this negotiation," they added, calling the pause requested by Tehran "disappointing" and urging "a faster pace".
"We now have a good starting line," an E3 source said, adding the next round would start discussing "the substance".
Iran's top negotiator, Ali Bagheri Kani, said on Twitter that good progress had been made in the negotiations.
"We have made good progress this week. We will convene a Joint Commission today and will continue talks after a break of a few days," he said.
Meanwhile, a US official said on Friday that the United States believes Iran's breakout time to producing enough highly enriched uranium for one nuclear weapon is now "really short" and alarming.
The talks in Vienna resumed last week after a five-month pause following the election of Iranian President Ebrahim Raisi.
Iran has gradually scaled back its compliance with the 2015 nuclear deal it signed with world powers in response to former US President Donald Trump’s withdrawal from the agreement in May of 2018.
The Islamic Republic has repeatedly demanded that the US lift sanctions imposed on Iran and also reassure Iran it will not abandon the deal again as a precondition for its returning to compliance with the deal.
(Israel National News' North American desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Israel National News articles, however, is Israeli time.)