Iran's leading nuclear official has ruled out any discussions over the country's nuclear programme during the upcoming talks with the world's big powers, while disclosing that a new uranium enrichment site had initially been built by the elite Revolutionary Guards as an ammunition depot.

The comments on Tuesday by Ali-Akbar Salehi add to the pessimism that talks on Thursday in Geneva with the US, Britain, Germany, France, Russia and China will bear any fruits and will further fuel international suspicions about the link between the country's nuclear and missile plans.

“We will never bargain about our sovereign rights,” Mr Salehi told a selected number of international media, including the Financial Times. “If we have the right to enrich uranium . .. convert uranium . . . have fuel fabrication . . . design reactors and manufacture reactors, we will do them and will not freeze them.”