Turkey called Russia's invasion of Ukraine a "war" on Sunday in a rhetorical shift that could pave the way for the NATO member nation to enact an international pact limiting Russian naval passage to the Black Sea.
Under the 1936 Montreux Convention, Turkey has control over the Dardanelles and Bosphorus straits that connect the Mediterranean and Black seas and can limit the passage of warships during wartime or if threatened.
