Photos show Russia's military buildup near Ukraine as Putin claims dominion over more of the region's sea and air

Moscow — Tension between Russia and the West has escalated further this week, with Russia staging more military exercises in the Black Sea and reportedly massing thousands of forces at Ukraine's border. In a clear sign of cooling relations, the United States' ambassador in Moscow confirmed he was leaving the country for "consultations" back in the U.S. 

Over 20 Russian vessels took part in the latest exercises along with Su-25SM3 attack aircraft, as part of a check of the fleet's forces, Russia's Black Sea Fleet said on Tuesday.  Russia also announced that it was closing the airspace over parts of Crimea and the Black Sea, saying the areas had been "declared temporarily dangerous for aircraft flights," Russia's Interfax news agency reported on Tuesday, citing an official notice sent to pilots.