Mediators say more talks to be held next week but no clear evidence two sides any closer on uranium enrichment

High-stakes talks between the US and Iran over the future of Tehran’s nuclear programme ended on Thursday without a deal, as the White House weighs a military operation that would mark its largest intervention in the Middle East in decades.

The Iranian foreign minister, Abbas Araghchi, claimed “good progress” had been made at the talks and Omani mediators predicted negotiations would reconvene at a technical level next week in Vienna.