Russia is considering arming its Baltic fleet with nuclear warheads for the first time since the cold war, senior military sources were quoted as saying by the Sunday Times. The warning came after Thursday's agreement between Poland and the United States that will see a battery of American missiles established inside Poland. The plan has infuriated Moscow and prompted a top Russian general to say Friday that the deal exposed Poland to attack, pointing out that Russian military doctrine permitted the use of nuclear weapons in such a situation. According to the British newspaper, the nuclear warheads could be supplied to submarines, cruisers and fighter bombers of the Baltic fleet based in Kaliningrad, a Russian enclave between Poland and Lithuania. The Times quoted a senior military source in Moscow as saying that although the fleet had suffered from under-funding since the collapse of communism, "That will change now." "In view of America's determination to set up a missile defense shield in Europe, the military is reviewing all its plans to give Washington an adequate response," said the source. Kurt Volker, the US ambassador to NATO, condemned the proposal. "It is really unfortunate that Russia chooses to react by putting nuclear warheads in different places - if indeed it does that - when the rest of the world is not looking at some kind of old-fashioned superpower conflict," he said, according to the Times.