SANGASTE, ESTONIA - MAY 18: Members of the British Duke of Lancaster's Regiment prepare to move out for an operation while participating in the NATO "Spring Storm" military exercises on May 18, 2014 near Sengaste, Estonia. The annual exercises, in which Estonian, Latvian, Lithuainian, U.S., British, Polish, Belgian and Danish troops are participating, are underway as sporadic fighting between Ukrainian and pro-Russian separatists continues in eastern Ukraine. (Photo by Sean Gallup/Getty Images)
