The Ukrainian president has proposed imposing martial law after Russian forces shot at and seized three Ukrainian navy vessels in the Black Sea. Russia had already blocked passage through the Kerch Strait, a narrow body of water nestled between Crimea and the Russian mainland, after three Ukrainian navy ships made what the Russian coast guard called an unauthorised crossing through Russian territorial waters. The incident began on Sunday after the Ukrainian navy claimed a Russian coast guard vessel rammed a Ukrainian navy tugboat, which was travelling with two Ukrainian navy artillery boats from Odessa on the Black Sea to Mariupol in the Sea of Azov, via the Kerch Strait.
