Ali Asghar Soltanieh, Iran's ambassador to the International Atomic Energy Agency (IAEA), was quoted by state television as saying that the bidding will be "open to all countries" willing to join the country's nuclear drive.

Iran insists its nuclear programme is simply a bid to generate electricity, but the country is widely suspected of also seeking the capacity to make nuclear weapons.

The regime had already announced in February that it was preparing to invite tenders for further nuclear power stations to be built in Bushehr, where Iran's first nuclear plant is currently being built with Russian assistance.

The latest announcement comes amid mounting tensions over the nuclear programme. The UN Security Council has given Tehran until April 28 to freeze uranium enrichment, a process to make reactor fuel which can be extended to make weapons.