Hossein Moussavian, quoted by the official IRNA news agency, did not rule out future talks with Washington, despite non-existant diplomatic relations since 1979.

"From our point of view, it is important that the Americans and Europeans interact in this process," Moussavian was reported as saying.

"The Europeans are making big efforts to bring the Americans into nuclear discussions. We have no objection to the Americans joining the Europeans in this process," he added.

But there was no need for direct US nuclear talks "at this stage," he said.

Last month, Iran agreed to suspend uranium enrichment in exchange for trade, technology and security rewards from Britain, France and Germany -- preventing its nuclear activities from being referred to the UN Security Council.

The deal was heavily criticised by the United States. It accuses arch-foe Tehran of covertly trying to develop nuclear weapons, a charge vehemently denied by Iran.