Russia says it has made its eighth and last fuel delivery for Iran's nuclear power plant at Bushehr.
Since the first delivery last month, Russia has sent a total of 82 tons of nuclear fuel to the Gulf port plant.
Iran says it hopes to have the power plant operating at 50 percent capacity by the middle of the year. But Russia says it doubts if the facility can be started up before the end of 2008.
The United States says the Russian fuel deliveries and the return of the spent fuel to Russia makes it unnecessary for Iran to enrich uranium on its own.
But Iran insists it has the right to make its own fuel for future power plants.
Washington and many of its allies fear Iran is planning to build a nuclear weapon with the enriched uranium - a charge Iran strongly denies.
The United Nations Security Council is considering a new sanctions against Iran for its refusal to give up its nuclear program.
Some information for this report was provided by AFP and AP.