Iran's Foreign Minister Hossein Amirabdollahian said in Moscow on Wednesday that he expected negotiations on the 2015 nuclear deal to restart in Vienna soon.
The deal, which gave Iran sanctions relief in return for limits on its nuclear programme, has been in doubt since 2018, when then-US president Donald Trump withdrew from the accord.
US President Joe Biden has indicated a willingness to return to the deal, but his Secretary of State Antony Blinken warned last week that time was running out and the ball was in Iran's court.
"We are now finalising consultations on this matter and will soon restore our negotiations in Vienna," Mr Amirabdollahian said after talks with Russian Foreign Minister Sergey Lavrov.
In Tehran, Parliament's national security and foreign policy commission spokesman Mahmoud Meshkini said the talks would resume "in coming days".
"The messages and signals from western countries point to the start of a new cycle of talks," Mr Meshkini told Iran's Tasnim news agency.
The Iranian side would be led by "the Foreign Ministry or the Supreme National Security Council", whose decisions must be confirmed by the supreme leader, Ayatollah Ali Khamenei.
"Normally, the country's broad strategic lines are defined by the Supreme Council and implemented by the foreign ministry," Mr Meshkini said.
Iran has gradually retreated from its nuclear commitments since 2019, a year after Mr Trump withdrew the US from the multilateral accord and began imposing sanctions.
Despite Mr Biden's decision to reverse the move, talks in Vienna to revive the accord have been at an impasse since June, when Iran's ultra-conservative new President Ebrahim Raisi was elected.
Mr Lavrov on Wednesday said that the negotiations "should be resumed as soon as possible" and called on the US to return to its obligations under the accord.
He said the international community was waiting for the US to "return to legal obligations of the nuclear deal" and end "illegal restrictions on Iran and all of its trading partners".