The European Union has welcomed an announcement by Iran that it is to suspend its uranium enrichment programme.
Iran made the move in an effort to resolve a dispute over whether its nuclear programme is a front for developing weapons.
Speaking after talks with British, French and German officials, Tehran's Chief negotiator Hassan Rohani said the suspension would remain in place until a long-term agreement is reached on the country's nuclear programme.
A European diplomat is quoted as saying that although the EU still has to digest the details of the agreement, the announcement opens a new chapter of relations between Iran and the EU.
Iran insists its nuclear activities are peaceful, but the US says they are part of a secret weapons programme.
Once the announcement is confirmed by the International Atomic Energy Agency, the freeze means the agency's board is unlikely to take the dispute to the UN Security Council for possible economic sanctions when it meets later this month.
