The local Mehr news agency reported Araghchi had arrived in the Omani capital Muscat for Saturday's negotiations, releasing a brief video showing the foreign minister disembarking from an Iranian government plane.

Araghchi will be leading what ministry spokesman Esmaeil Baqaei described as a delegation of diplomats and technical experts for indirect discussions with the US side.

President Donald Trump's special envoy to the Middle East, Steve Witkoff, will represent the United States in the talks.

The meeting follows two earlier rounds of Omani-mediated negotiations in Muscat and Rome starting on April 12.

The third round will include expert-level talks on Iran's nuclear programme, with Michael Anton, who serves as the State Department's head of policy planning, leading the technical discussions on the US side.

Iran's Tasnim news agency reported that deputy foreign ministers Kazem Gharibabadi and Majid Takht-Ravanchi will lead the technical talks on the Iranian side.

Baqaei said Friday that "progress in the negotiations requires the demonstration of goodwill, seriousness, and realism by the other side".

Araghchi said in an interview this week that Iran "will enter the negotiations seriously on Saturday, and if the other party also enters seriously, there is potential for progress".

Trump wrote a letter to Iran's supreme leader Ayatollah Ali Khamenei in March, urging talks while warning of potential military action if diplomacy failed.