The United States and the European Union are warning Russia not to annex Crimea after voters there overwhelmingly backed a referendum to leave Ukraine. Crimean authorities say 96.8 percent of voters supported the referendum to join Russia, but many members of the ethnic Ukrainian and Muslim Tatar minorities stayed home in a boycott. The Obama administration has threatened sanctions on Russia if Crimea follows through and secedes. But Russia has vowed to approve Crimea’s bid in a parliamentary vote. On Saturday, the Russian government vetoed a U.S.-backed Security Council resolution declaring the referendum invalid. Russian forces also seized a natural gas terminal in Ukraine, just outside Crimea’s regional border. The situation in Crimea has sparked the gravest crisis in East-West relations since the Cold War. We discuss the Crimea vote and its diplomatic fallout with three guests: Oliver Bullough, Caucasus editor for the Institute for War and Peace Reporting; Nicholas Clayton, a freelance journalist who has been reporting from Crimea and covering the South Caucasus since 2009; and Dmitri Trenin, director of the Carnegie Moscow Center.