Russian military units have been scrambled from their bases as part of snap drills ordered by President Vladimir Putin, the latest in a series of Russian war games amid tensions with the West over Ukraine.

The Defense Ministry said the maneuvers that began Monday will last for five days and involve forces of the Central Military District, a group of forces spreading from the Volga River all the way to eastern Siberia, along with air force and airborne units.

Gen. Sergei Koshelev briefed foreign military attaches about the exercise, saying they are aimed to check the troops' combat readiness and don't threaten any country. He described the maneuvers as "another snap check, similar to those that have been held in the past and will be held in the future."