"The process to install new [Iran-made] centrifuges to enrich uranium is continuing in Natanz," Gholamreza Agazade, also head of the Atomic Energy Organization of Iran, told Iran's ISNA news agency.
Iranian authorities have declined to specify the number of centrifuges in Natanz but Ali Larijani, Security Council Secretary, said the gas (uranium hexafluoride) was already being supplied to the centrifuges.
Mohammad Saidi, deputy chief of the Atomic Energy Organization of Iran, said the exact number of the centrifuges would be known after nuclear weapons inspectors of the International Atomic Energy Agency, the UN's nuclear watchdog, present their report in 20 days. Before April 9, two cascades with 164 centrifuges were officially in operation at Natanz.
Agazade said 50,000 centrifuges would be installed at the plant within two years. "If the international community fails to supply nuclear fuel to us, we will be able to meet our needs domestically," Agazade said.
Iran's nuclear research program, which Tehran resumed last January, aroused serious concerns among the international community. Western countries suspect Iran of pursuing a covert weapons program but Iran says it needs nuclear fuel for energy.
The uncompromising position of the Islamic Republic led to UN sanctions in December and March.