MOSCOW, Feb. 10 (Xinhua) -- Russian strategic bombers patrolled seas off northwestern Europe on Thursday amid military buildup by the North Atlantic Treaty Organization (NATO) near its borders.

Russian Defense Ministry confirmed that two Russian Tu-160 long-range bombers flew over the neutral waters in the Barents Sea, the Norwegian Sea and the Atlantic.

"The flights strictly complied with international regulations on the use of airspace over neutral waters, without violating the borders of other countries," the ministry's spokesman Igor Konashenkov said in a statement.

The Russian aircraft were closely followed at some stages of the the flights by NATO combat aircraft, including British jets, according to the spokesman.

Last month, Poland received about 1,000 U.S. soldiers and a tank brigade comprising some 3,500 servicemen and various weaponry.

NATO has also decided to deploy multinational battalions to the Baltic countries of Latvia, Lithuania and Estonia.

The bloc's military expansion poses a threat to Russia and greatly increases the danger of possible incidents, Russian Deputy Foreign Minister Aleksey Meshkov was quoted as saying by RIA Novosti news agency Thursday.