That would explain Russia's insistence on protecting Iran from sanctions as they build up their nuclear capabilities. The threat of a nuclear Iran increases the price of oil. At the same time, if Iran were nuclear, that would also be a situation that Russia could no longer control. That might explain Russia's more aggressive tone.
Iran should improve its cooperation with the International Atomic Energy Agency, Russian President Dmitry Medvedev's spokeswoman says.
"On the subject of sanctions, Russia's position remains unchanged. Russia still believes that Iran should more actively and broadly cooperate with the IAEA and other countries," spokeswoman Natalia Timakova told reporters on Tuesday.
"If these obligations are not fulfilled, no one can exclude the application of sanctions," AFP quoted Timakova as saying.
Russia has made such threats before. They've never followed through when push came to shove. Still, no one understands Vladimir Putin better than Garry Kasparov. If Kasparov is right, a nuclear Iran is not in Russia's interest. As such, if you follow Kasparov's theory, they will stop Iran from getting a nuke before it is too late. Such a move would serve all their purposes and be very shrewd as it would also mean they'd have that much more geopolitical leverage as well.