Demonstrators hold a Georgian national flag and a poster reading "Stop Moscow" during a rally in support of United Ukraine in Tbilisi, Georgia, Sunday, April 13, 2014. The US Ambassador to the United Nations, Samantha Power told ABC's "This Week" programe on Sunday that recent violence in Ukraine "bears the tell-tale signs of Moscow's involvement" and went on to say "It's professional, it's coordinated. There's nothing grassroots seeming about it". (AP Photo/Shakh Aivazov)