It is the second inspection of the uranium enrichment facility in central Iran conducted by the International Atomic Energy Agency (IAEA) since the beginning of 2007, the Fars news agency said.
Tensions continue to grow over the Iranian nuclear program as some Western countries, particularly the U.S., suspect Tehran is pursuing a covert weapons program since it resumed uranium enrichment in January 2006. But Tehran has consistently claimed it needs nuclear power for civilian power generation and is fully entitled to its own nuclear program.
Following President Mahmoud Ahmadinejad's statement Monday that the Islamic Republic had started producing nuclear fuel on an industrial scale, reports have circulated that as many as 3,000 centrifuges had been launched at the Natanz center.
However, Iranian information agencies denied the figure later that day, citing Iranian energy and security officials as saying it was too early to announce their exact number.
"Iran's plans regarding the uranium enrichment center in Natanz are not only confined to fixing 3,000 centrifuges, but they suggest that 50,000 such devices will be put into operation," Iranian information agency IRNA quoted Gholamreza Aghazadeh, who is also the head of the country's Atomic Energy Organization, as saying.
The vice president explained that he had deliberately refrained from specifying the number of centrifuges while speaking during celebrations to honor the national day of nuclear technology in Iran Monday.
"I was anxious that speculations could appear, particularly in the Western media, that the Iranian nuclear program will be completed with the installation of only 3,000 centrifuges," the official said, adding that equipment at the center was meant precisely for 50,000 units.
The IAEA experts are expected to work at the Natanz center until April 17.
Meanwhile, Russian Foreign Minister Sergei Lavrov said Tuesday that Moscow was unable to confirm whether Iran has started uranium enrichment on an industrial scale, and has asked the IAEA for a report with an assessment of the situation.
"We take Iran's nuclear program seriously and would like to base [our assumptions] on facts and not on emotional political gestures, which have been frequent on various sides," Lavrov said.
"However, we cannot confirm as yet that practical [uranium] enrichment has started at new cascades [of centrifuges]," the minister said.
