The United Nations nuclear watchdog confirmed on Monday that Iran has started enriching uranium at an underground site and said all atomic material there was under its surveillance.
Diplomats in Vienna, home of the UN International Atomic Energy Agency (IAEA), earlier said Iran had begun refining uranium to a fissile purity of 20 percent at Fordow near the Shi'ite Muslim holy city of Qom.
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"The IAEA can confirm that Iran has started the production of uranium enriched up to 20 percent...using IR-1 centrifuges in the Fordow Fuel Enrichment Plant," agency spokeswoman Gill Tudor said in an e-mail.
"All nuclear material in the facility remains under the Agency's containment and surveillance," she said.
Iran has said for months that it is preparing to move its highest-grade
uranium refinement work to Fordow from its main enrichment plant at
Natanz, and sharply boost capacity. Enriched uranium can have both
civilian and military uses.
The decision by the Islamic Republic to conduct sensitive atomic
activities at the underground site - offering better protection against
any enemy attacks - could complicate diplomatic efforts to resolve the
long-running row peacefully.
On Sunday, an Iranian newspaper quoted the head of Iran's Atomic Energy
Organization as saying Iran would in the "near future" start enriching
uranium at Fordow.
The United States and its allies say Iran is trying to develop the means
to make atomic bombs, but Tehran insists its nuclear program is aimed
at generating electricity and isotopes for medical treatment.