The Southern Military District, where the exercises will take place, includes the regions bordering Ukraine and the Crimean Peninsula, which Russia annexed last year. But the military didn't say exactly where the maneuvers were being held.
The Defense Ministry said today the exercises would last for more than a month and involve more than 2,000 troops and 500 weapons systems, including air defense missiles. The maneuvers would simulate fending off massive air and missile attacks.
Lt Gen Ben Hodges, the commander of US Army Europe, has said earlier this week that Russia has 12,000 troops in eastern Ukraine.
Russian Deputy Defense Minister Anatoly Antonov acerbically rejected the claim today. "Why 12,000 and not 20,000 or 25,000? Why go small?" he told reporters.
Antonov argued that more than 30 flights by foreign military observers over Russian territory have failed to yield any evidence to corroborate Western accusations.