The main stage of the "Zapad-2021" military exercise involves the army corps and military units of the Western Military District of the Russian Federation, as well as the military units of Armenia, Belarus, India, Kazakhstan, Kyrgyzstan and Mongolia. Armenia participates in the military game as a contingent consisting of tank, motorized rifle and missile-artillery subdivisions.

The training and combat operations are based on the experience of recent military operations, in particular, in the Syrian Arab Republic and the Republic of Artsakh. Also, new ways and methods of joint actions of troops were developed.

The "Mulino" military training ground makes it possible to conduct military exercises using firearms, military equipment, artillery and air defence systems, aviation, as well as Iskander-M operational-tactical missile systems.