President Vladimir Putin has ordered snap drills to check the Russian military's readiness to quickly mobilize its forces.

Russia's Defense Minister Sergei Shoigu said that the maneuvers that began Tuesday will last for a week. He said the exercise is aimed at checking the readiness of reserve military units and weapons depots.

Shoigu said the war games will assess the "mobilization readiness" of the Russian armed forces and the top brass' ability to quickly make military reserves ready for action.

He noted that special emphasis will be given to "planning the use of military forces in various crisis situations."

The maneuvers are the latest in a steady series of drills intended to strengthen the military's readiness amid tensions with the West over Ukraine.