"This fuel delivery provides Iran with one more reason to suspend their nuclear program. If the Russians are providing the Iranians fuel, the Iranians have no reason to enrich uranium themselves," said spokesman Gordon Johndroe.

His comments came after Moscow announced the start of nuclear fuel deliveries for Iran's first atomic power station, brushing aside US and Israeli claims that Tehran harbors secret bomb-making plans.

"We have been in contact recently with the Russians with regards to their plans and we also note the IAEA involvement," said Johndroe, referring to the UN's watchdog International Atomic Energy Agency (IAEA).

Johndroe said the shipments were not a sign of fissuring international support for UN sanctions aimed at forcing Iran to freeze uranium enrichment, which can be a key step towards making a nuclear weapon.

"The international community remains united in its desire to see the Iranian regime comply with its United Nations Security Council resolutions," the spokesman said.

Russia's state-run Atomstroiexport announced in a statement that it began delivery of fuel "for the initial installation at the future Bushehr power station" on December 16.

The delivery process will take up to two months to complete, Atomstroiexport said, with the Russian-built station starting to generate electricity in approximately six months time.

The still-unfinished Bushehr is the jewel in the crown of Iranian President Mahmoud Ahmadinejad's nuclear power ambitions.

Iran confirmed the Russian shipment and in a fresh show of defiance toward the West, repeated that it would refuse UN demands to give up work on enriching uranium.

Israel and Western governments, led by the United States, have long argued that Iran's civilian program is being used as cover for a bomb-making project.

Russia rejects this and Moscow's position was bolstered earlier this month when the US intelligence community contradicted the White House by reporting that Iran had stopped a drive for nuclear weapons in 2003.