Iran says nuclear deal is possible if Washington is realistic

"If they demonstrate seriousness of intent and do not make unrealistic demands, reaching agreements is possible," Araqchi told a news conference in Moscow after talks with Foreign Minister Sergei Lavrov of Russia.

Iran had noted the United States' seriousness during a first round of talks on the deal, which took place in Oman last week, Araqchi said. The second round is set for Saturday in Rome.

Iran told the United States in talks last week it was ready to accept some limits on its uranium enrichment but needed water-tight guarantees that President Donald Trump would not again ditch a nuclear pact, a senior Iranian official said on Friday.

Trump has threatened to attack Iran if it does not reach a deal with the U.S. over its nuclear programme, which Iran says is peaceful but the West says is aimed at building an atomic bomb.

"I'm for stopping Iran, very simply, from having a nuclear weapon. They can't have a nuclear weapon. I want Iran to be great and prosperous and terrific," Trump told reporters on Friday when asked if he would consider letting Tehran keep a civil nuclear program.

Lavrov said Russia was "ready to assist, mediate and play any role that will be beneficial to Iran and the U.S.A."

Moscow has played a role in Iran's nuclear negotiations in the past as a veto-wielding U.N. Security Council member and signatory to an earlier deal that Trump abandoned during his first term in 2018.

Iranian Supreme Leader Ali Khamenei sent Araqchi to Moscow with a letter for President Vladimir Putin to brief the Kremlin about the negotiations. Araqchi will also visit Beijing within the next few days, the Iranian state news agency IRNA reported on Friday, without providing further details.