"The issue of suspension cannot be discussed any more, we have passed this point and it is not relevant. Iran's position is clear on this point," government spokesman Gholam Hossein Elham told reporters.
"The government view is that the issue is over," he added in reaction to a new report by UN nuclear watchdog the International Atomic Energy Agency.
The IAEA on Monday expressed "serious concern" that Tehran was still hiding information about alleged studies into making nuclear warheads, as well as defying UN demands to suspend uranium enrichment.
Washington and its European allies fear Iran wants to use the sensitive process of uranium enrichment to make an atomic weapon, but Tehran insists its drive is entirely peaceful and has refused to freeze such efforts.
Elham was speaking two days after Foreign Minister Manouchehr Mottaki said he expected European Union foreign policy chief Javier Solana to visit Tehran "soon."
He said precise details of Solana's trip to Tehran have not yet been finalised.
A US official said last week that six major world powers have completed a "refreshed" offer they intend to present to Iran in a bid to end the long-running nuclear standoff.
The six are the five permanent members of the UN Security Council — Britain, China, France, Russia and the United States — plus Germany.
The United States has pursued a two-track policy of UN and other sanctions against Iran for its failure to halt uranium enrichment, while also holding out offers of economic and other incentives if it stops such work.
The enrichment process is used for power generation but at highly refined levels can also be used to build the core of a nuclear weapon.
