"We are now finalising consultations on this matter and will soon restore our negotiations in Vienna," he told reporters after talks with Russian Foreign Minister Sergei Lavrov.

The 2015 nuclear deal gave Iran sanctions relief in return for tight controls on its nuclear programme.

In 2018, then-US President Donald Trump withdrew from the multilateral accord and began reimposing sanctions.

Tehran has gradually rolled back its nuclear commitments since 2019.

US President Joe Biden reversed Trump's decision to pull the United States from international negotiations on curbing Iran's nuclear ambitions.

But talks in Vienna to revive the deal have been at an impasse since June, when Iran's ultraconservative new President Ebrahim Raisi was elected.

Lavrov said Wednesday that the negotiations "should be resumed as soon as possible," and called on the United States to return to its obligation under the accord.

Russian's foreign minister said that the international community was waiting for the United States to "return to legal obligations of the nuclear deal" and end "illegal restrictions on Iran and all of its trading partners."