Moscow, September 21 (KCNA) -- The Russia-Belarus military strategic maneuvers, codenamed "Federation Shield-2011", entered the second stage in Arkhangelsk, Russia, on Tuesday, according to a spokesman for the Russian Air Force.

The second stage is aimed at evaluating the efficiency of the Russia-Belarus anti-aircraft system.

The principal mission of the system is to jointly defend the airspace of the two nations, the spokesman said.