Atomstroiexport said the first delivery of the 163 containers of uranium-235 arrived on 16 December and the full delivery will take two months. Tehran confirmed the delivery the following day.

The Russian firm said the containers were delivered by the International Atomic Energy Agency after they had been inspected.

Iran's nuclear programme has been at the centre of a political rift with the West. The US and Russia said that due to the shipment, Iran would no longer have a reason to enrich uranium domestically.

US President Bush said he would support the trade as long as Iran returns the spent uranium to Russia for reprocessing. "If the Russians are willing to do that, which I support, then the Iranians do not need to learn how to enrich," said Bush.

The Bushehr site will house Iran’s first atomic power plant and there are plans for more plants to be developed.

The Nuclear Power Production & Development Company, a subsidiary of Iran Atomic Energy Organisation, issued tenders in April for two additional 1,100-1,600 MW plants in the Bushehr region.