Russia will take retaliatory measures if NATO deploys four extra battalions in Poland and the Baltic states and it will reinforce its western and southern flanks with three new divisions by the year-end anyway, officials said. U.S. Defense Secretary Ashton Carter said on Monday that NATO was weighing up rotating four battalions of troops through eastern member states amid rising tension in the Baltic.

Russia has scrambled jets to intercept U.S. reconnaissance planes in recent weeks and made simulated attack passes near a U.S. warship in the Baltic Sea. Andrei Kelin, a department head at Russia’s Foreign Ministry, said on Wednesday that the proposed NATO deployment spoken of by Carter was a source of concern for Moscow. READ MORE