International Atomic Energy Agency documents revealed that Iran began a secret nuclear program during the tenure of Mir Hossein Mousavi, the opposition leader running against President Mahmoud Ahmadinejad.
The documents, which Iran transferred to the IAEA several years ago, show that Tehran decided in 1987 to purchase the centrifuges it is using to enrich uranium.
Mousavi, who is seen as a moderate candidate in the West, served as Iran's prime minister between 1981 and 1989, and while that position has since been eliminated from Iranian politics, it was an executive position that was similar in nature to the current presidential role.
One of the documents revealed that the then-head of Iran's atomic energy organization requested Mousavi's approval for purchasing the centrifuges on the black market. Iran subsequently acquired the centrifuges through the smuggling ring of Pakistani scientist Abd al-Qadir Khan.
The document from March 1987, classified as secret, said that Iran's then-chief atomic energy official said Tehran's activities related to Khan must remain secret. The document appeared as part of a quarterly report the IAEA issues as part of its supervision of Tehran's nuclear program.
Iran transferred the documents to the energy agency after it learned in 2002 that Tehran was secretly developing the nuclear facility in Natanz, where the centrifuges bought on the black market are being used to enrich uranium - in opposition to its agreement with the IAEA.
As part of its cooperation with the agency, Tehran must prove that its nuclear energy program is meant for peaceful purposes and not for developing nuclear weapons, as Israel, the United States and other Western nations believe to be the case.
Fervent, youthful supporters of Mousavi accused the president of undermining Iran's international standing with his confrontational style and of devastating the economy.
Sources: Iran denies UN nuke agency camera request
Iran has rebuffed a bid from the UN nuclear monitoring agency to beef up its monitoring ability at an important atomic site as it tries to keep track of the country's rapidly growing uranium enrichment capabilities, diplomats said Thursday.
The diplomats said the Islamic Republic in recent weeks turned down a request from the International Atomic Energy Agency to place one or more additional surveillance cameras at the Natanz enrichment site.
In addition, they said, the agency was concerned Iran would use its recent denial of access to Natanz to agency inspectors seeking a surprise visit as a precedent, further hampering the UN agency's need to increase its oversight.
IAEA spokesman Marc Vidricaire said the agency would have no comment.
An IAEA report circulated last week said nearly 5,000 centrifuges were now enriching at Natanz - about 1,000 more than at the time of the last agency report, issued in February - with more than 2,000 others ready to start enriching.
Iranians prepare to go to the polls
Iran's raucous election campaign fell silent a day before the vote as rallies were barred Thursday to give the public time to reflect on whether they want to keep hard-line President Ahmadinejad in power or replace him with a reformist more open to closer ties with the West.
The campaign reached a crescendo in the past few days with dueling rallies by supporters of Ahmadinejad and his main challenger, Mousavi, that drew tens of thousands into the streets of Tehran.
The stakes are extremely high for Iran - the new leader must decide how to respond to U.S. President Barack Obama's offer for dialogue after a nearly 30-year diplomatic chill. The Obama administration is cautiously watching the vote for signs the Islamic Republic may be willing to engage, but U.S. officials have meager expectations for change.
Tehran residents went about removing posters and banners from buildings and cars as campaigning officially ended early Thursday.
In the final hours of the fierce contest, Mousavi got a sharp warning from the country's powerful Revolutionary Guard that authorities would crush any attempt at a popular revolution inspired by the huge rallies and street parties calling for more freedoms.
The threat Wednesday reflected the increasingly tense atmosphere surrounding the up-for-grabs election. It also marked a sharp escalation by the ruling clerics against Mousavi's youth-driven campaign and its hopes of an underdog victory.
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