President Vladimir Putin lays flowers during a ceremony marking Victory Day in the Crimean city of Sevastopol on Friday. It was his first visit to the region since Russia annexed it in March. Maxim Shemetov/Reuters/Landov hide caption

itoggle caption Maxim Shemetov/Reuters/Landov

President Obama and Russian President Vladimir Putin meet in Enniskillen, Northern Ireland, on June 17. Obama has strongly condemned Russian intervention in Ukraine but has not yet announced a concrete response. Evan Vucci/AP hide caption

itoggle caption Evan Vucci/AP

Russian tycoon Boris Berezovsky talks to the media on Aug. 31, 2012, after losing his case against Russian oligarch Roman Abramovich in London. Berezovsky was found Saturday dead at his home in Britain. Sang Tan/AP hide caption

itoggle caption Sang Tan/AP