NATO weighs four battalions in Eastern states to deter Russia - U.S.

U.S. Secretary of Defense Ash Carter testifies on operations against the Islamic State, on Capitol Hill in Washington, U.S., April 28, 2016. REUTERS/Jonathan Ernst

STUTTGART, Germany (Reuters) - The NATO alliance is weighing rotating four battalions of troops through Eastern member states, U.S. Defense Secretary Ash Carter said on Monday, in the latest proposal by allies to guard against aggressive behaviour by Russia.

The Baltic states - Estonia, Latvia and Lithuania - which joined NATO in 2004, have requested greater presence of the alliance, fearing a threat from Russia after it annexed the Crimea peninsula from Ukraine in 2014.