Araghchi made the remark in a joint press conference with his Russian counterpart Sergei Lavrov in Moscow on Friday, a day ahead of a second round of indirect talks between Tehran and Washington, which is scheduled to be held in the Italian capital, Rome.

“We will only negotiate over the nuclear issue and other topics will not be included in these negotiations,” he said.

“I believe there is a possibility of reaching an agreement if they [Americans] demonstrate seriousness of intent and make no unrealistic and unreasonable demands,” he added.

The top Iranian diplomat cited Washington’s threats and its so-called maximum pressure policy as Iran’s reasons for holding indirect talks with the US.

He, however, emphasized, “The path of diplomacy is open. Indirect talks are not complicated and can lead to an agreement.”

He said Tehran spotted a certain level of the United States' seriousness during the first round of talks in the Omani capital Muscat on April 12.

The Iranian foreign minister cast serious doubt over US intentions following Washington’s contradictory positions.

"We have serious doubts about the intentions and motivations of the American side but we will participate in tomorrow's negotiations with full seriousness and determination," he pointed out.

He once again voiced Tehran’s full readiness to find a peaceful solution to its peaceful nuclear program.

Speaking to reporters in Moscow earlier on Friday, Araghchi said Tehran will assess and decide on the path ahead of negotiations based on the approach of the United States in the second stage of indirect talks in Rome.

Araghchi and Steve Witkoff, the US president’s special envoy for Middle East affairs, led the first round of indirect talks in Muscat. Both sides described the talks as positive and constructive.

On Tuesday, Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei said the indirect talks between Iran and the US in the Omani capital have been “implemented well in their initial steps,” but added that the Islamic Republic is “very skeptical” of the other side.

During his first term in office, US President Donald Trump withdrew the United States from a previous agreement on Iran’s nuclear program and launched a maximum pressure campaign against the country.

Trump restored that policy after returning to the White House for a second term in January, but he has since signaled a willingness to make a new deal to replace the 2015 deal, officially called the Joint Comprehensive Plan of Action (JCPOA).

On March 12, Trump sent a letter to Iran’s leadership, asking for negotiations to reach a new deal and threatening military action if Tehran refused.

Iran has ruled out direct negotiations with the US under pressure and threats, but said indirect talks remain an option.

Ayatollah Khamenei’s message conveyed to Putin

Elsewhere in the presser, Araghchi said during his Thursday meeting with Russian President Vladimir Putin, he handed over a message from Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei to him which included various bilateral and regional issues.

The top Iranian diplomat noted that he held “useful” talks with the Russian president, which demonstrate that Tehran and Moscow are advancing relations.

He said Putin was officially invited to travel to Tehran and expressed hope that the visit would take place this year.

He noted that Iran and Russia have drawn up plans to promote economic cooperation regardless of sanctions imposed on both countries.

"Of course, this does not mean that the two countries recognize the legitimacy of the sanctions but they have designed their economic cooperation in such a way that even in the presence of sanctions, they can achieve desirable results,” Araghchi explained.

Russia ready to play any role in Iran-US talks: Lavrov

The Russian foreign minister said his country is ready to play any role in the negotiations between Iran and the US on a potential nuclear deal.

“We are ready to help, mediate and play any role that, from Iran's point of view, will be useful and that will be acceptable to the United States,” Lavrov added.

“We proceed from the fact that the only option for an agreement, as the [Iranian] Minister just said, is an agreement exclusively on nuclear issues,” he said, stressing that it is “a fundamental point.”

The Russian foreign minister also noted that Putin was “very pleased” with Thursday’s meeting with Araghchi.

“Yesterday's meeting emphasized the unprecedented dynamics of our political dialogue,” Lavrov said.