The Bushehr nuclear power plant in Iran was loaded with the first fuel on Saturday but the reactor will be started up later this year, the head of the Russian Federal Atomic Energy Agency (Rosatom) said.

"Today we begin the physical launch of the Bushehr power plant in Iran," Sergei Kiriyenko told a launch ceremony.

"The fuel is being put in the reactor chamber. From now on the reactor is an [operational] nuclear power plant," Kiriyenko said.

He stressed that the reactor can only be used for civilian purposes.

The project of the Bushehr nuclear power plant is unique, he said.

"The construction of the plant began in 1974. The uniqueness of the project consists in the fact that specialists succeeded in building the plant on the old foundations... laid down by a German company more than 30 years previously," he said.

The reactor will be started up before the end of the year, Rosatom head said, adding that "everything is going to plan."

The physical launch will include several stages, each of which will need permission from the Atomic Energy Organization of Iran (AEOI), he added.

AEOI head Ali Akbar Salehi described the day as "historic" and expressed his gratitude to Russia for the country's help in building the Bushehr power station.

Iran will hold nationwide celebrations to mark the launch of its first nuclear power station, promoting it as a victory over its enemies.

Experts say Bushehr should begin to produce electricity in one month's time.

The construction of Bushehr has taken 35 years and has been dogged by delays.

Russia signed a contract with Iran to complete construction in February 1998.

Under a bilateral agreement, which received approval from the United States, Russia will operate the plant, supplying its fuel and taking all the spent fuel. Russian Foreign Minister Sergei Lavrov said earlier this week that the Bushehr plant contributes to the nonproliferation regime.

However, Salehi said the Islamic republic is nevertheless set to continue its uranium enrichment program.

"The Bushehr plant has a lifespan of 60 years and we plan to use it for 40 years. Suppose we buy fuel for 10 years from Russia, what are we going to do for the next 30 to 50 years?" Salehi was quoted by the official Iranian news agency IRNA as saying on Friday.

"We now have enough nuclear fuel for the reactor for one year," he said. "One third of that [amount] has to be replaced every year."

Salehi said that Iran will be able to produce some 30 tons of enriched uranium at the Natanz enrichment facility once all the necessary equipment is installed.

Iran's only nuclear reactor other than Bushehr is a research reactor in Tehran that produces medical isotopes. Iran began a program to enrich uranium to 20% for the Tehran reactor earlier this year.

Iran needed to build more nuclear power plants, Salehi said, so it would also require more fuel. He said previously that Iranian President Mahmoud Ahmadinejad had ordered 10 new enrichment facilities to be built.

Western powers suspect Iran of pursuing nuclear weapons under the guise of its nuclear program, a charge Tehran strongly denies, saying the program is aimed at the peaceful generation of civilian energy.

On June 9, 2010, the UN Security Council approved a fourth round of sanctions against Iran over its nuclear program, including tougher financial controls and an expanded arms embargo, as well as an asset ban on three dozen companies and a travel freeze on individuals.

Later, the United States and the European Union imposed extra sanctions against Iran, including tougher restrictions on the energy sector and a tougher trade embargo.

The construction of Bushehr has not been affected by the sanctions.

BUSHEHR (Iran), August 21 (RIA Novosti)