TEHRAN, Iran - Iran said yesterday that it would begin operation of its first nuclear power plant next summer using half of the plant's 1,000-megawatt capacity, the official news agency IRNA reported.

Iranian Foreign Minister Manouchehr Mottaki said the Russians, who are helping build the light-water reactor in the southern Iranian town of Bushehr, will have completed nuclear fuel shipments by the summer, paving the way for its launch.

After months of delay, Russia began shipping nuclear fuel to Bushehr in mid-December and completed its second delivery Friday. The Iranians have said that Russia would send a total of 82 tons of nuclear fuel in eight shipments.

The process was held up by Russian claims that Iran had delayed construction payments for the reactor, but many observers suggested that Moscow also was unhappy with Tehran's unwillingness to assure the international community that it was not developing nuclear arms.

Tehran heralded the initial shipment as a victory, saying it proved that the country's nuclear program was peaceful, not a cover for weapons development as alleged by the United States and some of its allies.

The United States initially opposed Russian participation in building the Bushehr reactor and supplying it with fuel, but reversed its position about a year ago to obtain Moscow's support for the first set of U.N. sanctions against Iran.

Washington also was influenced by Iran's agreement to return spent nuclear fuel from the reactor back to Russia to ensure that Iran doesn't extract plutonium to make atomic bombs.

Russia's decision to begin shipping nuclear fuel to Iran followed a recently released U.S. intelligence report that concluded that Tehran had stopped its nuclear weapons program in late 2003 and had not resumed it since. Iran says it never had a weapons program.