In Donetsk, Russian pro protesters occupy the administration building. Ukraine: What should the Europeans and the Americans do?

                                                   Ukraine problems:

Ukraine plunged into instability: government buildings are controlled by pro-Russian in several cities of the East, and the West, as the central government in Kiev, seem powerless. Do you think the Europeans and Americans have to increase sanctions and their response to this situation? How can they manage one of the worst crises in Europe since the end of the Cold War?