MINSK (Reuters) – The United States and Russia will sign a deal this year to cut vast Cold War arsenals of nuclear weapons but may miss an early December deadline, a Kremlin source told Reuters on Friday. Diplomats from the two biggest nuclear powers are trying to prepare a new agreement on cutting atomic weapons before the 1991 Strategic Arms Reduction Treaty expires on December 5. The new accord will be signed "in a European country" in December, the Kremlin source told Reuters in Minsk, where President Dmitry Medvedev was meeting regional leaders. "We may not be able to do...