The Security Council still needs to wait for the IAEA report to be issued in March before considering actions against Iran. When that time comes, there may not be any agreement amongst council members about what action, if any, to take. Russia and/or China could simply veto sanctions if they want.
We can't forget that Russia has been having far worse problem with Islamic fundamentalists than we have. They have had continuous terror attacks and have responded in kind. They are much closer to Iran and have more to lose and gain than we do. They don't want to have Iran as an enemy, but I'm sure they don't want Iran to get a dirty (or "clean") bomb to deliver to radicals in Chechnya either. With the unstable politics in Iran, it's a touchy game.