Those troops remain positioned so close , and are so heavily armed , that the U.S. and NATO calculate they could `` roll across '' eastern Ukraine in three to five days , one official said . The USS Donald Cook will be in the Black Sea by Thursday . A Russian Su-24 jet fighter flies over a U.S. Navy destroyer during an exercise on March 27, 2016 near Sevastopol, Crimea. NATO representatives will meet April 15 to discuss the situation .
The USS Donald Cook will be in the Black Sea by Thursday . A Russian Su-24 jet fighter flies over a U.S. Navy destroyer during an exercise on March 27, 2016 near Sevastopol, Crimea. NATO representatives will meet April 15 to discuss the situation .