By Kerstin Gehmlich
PARIS - Iran has conducted successful experiments on a crucial triggering mechanism for a nuclear weapon, an exiled opposition group said on Thursday.
President Bush on Wednesday renewed his accusation that Iran was seeking to develop atomic weapons and called it the "world's primary state sponsor of terror."
Tehran dismisses the accusations and says its atomic ambitions are limited to the peaceful generation of electricity.
The National Council of Resistance of Iran (NCRI), which wants to oust Iran's clerical rulers and has given accurate information on its nuclear sites in the past, said Iran was close to producing the 'neutron initiators' that spark the chain reaction in a bomb.
"Tehran has already succeeded in using beryllium in conjunction with polonium-210 for large scale laboratory testing purposes, and it is getting very close to the point of industrial production," Mohammad Mohaddessin of the NCRI told a news conference in Paris.
Diplomats have already said there is evidence that Iran has bought small quantities of beryllium and tried to buy much more, and that the International Atomic Energy Agency's (IAEA) is examining this as part of a two-year investigation of Tehran's nuclear program.
Beryllium also has many innocent uses, but Mohaddessin said Iran had not only secured significant quantities but also tried to conceal its purchases from the IAEA.
"Tehran currently has enough beryllium to produce initiators for a dozen nuclear bombs," he said.
He said the laboratory tests had been conducted at the Lavizan II site close to Tehran by experts from the Malek-Ashtar Industrial university, which is run by the Defense Ministry.
Germany, France and Britain, acting for the European Union, have been urging Iran to permanently scrap the uranium enrichment that could give it the potential to make nuclear explosives in return for political and economic incentives.
Washington takes a harder line and wants Iran to be reported to the U.N. Security Council for possible sanctions.
The NCRI is a coalition of exiled opposition groups. The State Department lists it and its armed wing, the People's Mujahideen, as terrorist organizations.