A third round of talks on Russia’s offer to enrich uranium for Iran has ended with no clear breakthrough. “We are basically in agreement, but the details have to be worked out carefully,” said Ali Larijani, the chief Iranian nuclear negotiator.Russia’s offer is aimed at easing Western fears that Iran is planning to develop nuclear weapons. Moscow would enrich uranium to the level Iran says it needs to fuel power stations, but not to the higher grade needed for weapons. The Iranian delegation is set to leave Moscow today. A spokesman said there would be more talks before their departure. A UN nuclear watchdog report has said it cannot confirm whether Iran’s nuclear programme is legitimate or not. That report will be presented to the Security Council in less than a week, and sanctions could follow if it is decided that Iran has not co-operated with the international community’s demands.