If it’s interested, the means are there. If not, there isn’t much that either the OSCE or the Security Council can do about it. Certainly, the United States and Europe (if it is able to reach some kind of coordinated position) can use economic and political pressure to make Russia’s life uncomfortable. Equally certainly, they don’t have sufficient leverage to force Russia to pull out of Ukraine if it really doesn’t want to — and is prepared to pay the price.