Russia has trained hundreds of Iranian nuclear scientists and blocked international action against Tehran. But beneath the surface, there is profound distrust.
Russia built Iran's first nuclear power plant, once sold Tehran sophisticated weaponry, and refuses to back further international sanctions over Iran's controversial nuclear program, but this apparent coziness belies years of suspicion and growing distance between the two nuclear powers.
Despite the fact that Russia is training hundreds of nuclear scientists to operate the Bushehr plant, Russian analysts say that Moscow has contributed little to Iran's recent strides in uranium enrichment and nuclear technology.
Iran has been locked for months in negotiations with world powers over limiting its nuclear program, as Israeli leaders have threatened to conduct military strikes against Iranian nuclear facilities. Russia straddles both camps, but has its own turbulent history with Iran that complicates its role.
Gone are the dangerous, free-wheeling 1990s, when the collapse of the Soviet Union left legions of nuclear and missile engineers without work and willing to sell their services to the highest bidder – with Iran reported to be a frequent destination.
And the ranks of Iranian students studying nuclear and other physical sciences in Russia was thinned out years ago due to official concerns about spying and the ultimate purpose of the Islamic Republic's expertise, Russian experts say.
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