Vast stretches of Russian coast have been tarred by heavy fuel oil from two freighters that foundered in a storm.

Russia continues to suffer military defeats in the strategically vital Black Sea, one of Moscow's most crucial avenues for political and economic influence into the Mediterranean and beyond.

Fresh oil started pouring from a stricken Russian tanker in the Black Sea on Friday, said officials in Moscow, as Ukraine warned of "terrible environmental consequences" from the spill. Heavy fuel oil ...