Senior US and Iranian officials are set to continue discussions after talks in Oman, the Iranian foreign minister says, amid a crisis that had raised fears of a conflict between the countries.

Abbas Araghchi said the mediated discussions were a 'good beginning' and 'exclusively nuclear', and the negotiators would now return to their capitals for consultations.

Ahead of the talks, US officials indicated they also wanted to discuss Iran's ballistic missiles and support for regional armed groups, underscoring the gaps between the countries' positions.

There has been no immediate US reaction.

The talks came against the backdrop of a US military build-up in the Middle East in response to Iran's violent repression of nationwide protests, which human rights groups say killed many thousands of people.

President Trump has threatened to bomb Iran if a deal is not reached and has sent thousands of troops, including an aircraft carrier and fighter jets, to the region.

In retaliation, Iran has vowed to respond with force to any attack.

Speaking to Iranian state television, Araghchi noted an 'atmosphere of mistrust' that 'must be overcome', with further talks dependent on future consultations.

Oman's Foreign Minister Badr Albusaidi mediated the discussions, aiming to clarify both sides' positions and identify areas of potential progress.

With the complexities of their relationship evident, the historical context of these talks may indicate a crucial moment for both nations, especially as Iran's position remains increasingly vulnerable amid domestic unrest.