The Montreux Convention Regarding the Regime of the Straits is a 1936 agreement that gives Turkey control over the Bosporus Straits and the Dardanelles and regulates the transit of naval warships. The Convention gives Turkey full control over the Straits and guarantees the free passage of civilian vessels in peacetime. It restricts the passage of naval ships not belonging to Black Sea states. The terms of the convention have been the source of controversy over the years, most notably concerning the Soviet Union's military access to the Mediterranean Sea.