Crimea is a peninsula located on the northern coast of the Black Sea. With the collapse of the Soviet Union in 1991, Crimea became part of the newly independent Ukraine, leading to tensions with neighboring Russia.
In 1954, Crimea was transferred to the Ukrainian Soviet Socialist Republic as a symbolic gesture by Soviet leader Nikita Khrushchev. Following the breakup of the Soviet Union in 1991, Crimea became part of the independent Ukraine. Russia's Black Sea Fleet is stationed in Sevastopol and the southern tip of the peninsula continues to be a Russian stronghold in the region. Throughout the last decades tensions between the two neighbors have occasionally flared, but nothing like the escalation and mobilization of troops in March 2014.
Leaders from the G7 group of industrialized nations have said they will consider further measures against Russia, if necessary, over the Ukraine crisis. Russian President Vladimir Putin had been excluded from the talks.
Leaders of the G7 nations have gathered in Brussels for a summit that is likely to be dominated by the crisis in Ukraine. Russia is notably absent after being suspended from the group following the annexation of Crimea.