"It seems evident they should be more active" in "resolving all issues related" to the accord, Lavrov told reporters at the United Nations in New York.

Lavrov added that he hoped negotiations in Vienna among Iran, Russia, China, France, Britain and Germany would resume "as soon as possible."

The talks, brokered by the Europeans, seek the return of the United States to the 2015 agreement trashed by former president Donald Trump -- as well as Iran's return to full compliance.

Trump pulled America out in 2018, reinstating sanctions on Iran that Washington had lifted as part of the agreement.

Since then, Tehran has also retreated from many of its commitments.

Trump's successor Joe Biden has indicated he wants to return to the deal, but his administration has expressed impatience at the stalled talks.

Discussions between Iran and the remaining five parties aimed at reviving the deal began in Vienna in April but have been suspended since June, when ultraconservative Ebrahim Raisi was elected president.

Hopes of reviving the deal were kept alive earlier this month when Iran agreed to a new compromise with the UN nuclear agency on the monitoring of its nuclear facilities.

Iran's foreign minister, Hossein Amir-Abdollahian, said Friday the talks would resume "very soon," but the United States said Tehran had not been specific about the timeframe.