"During the course of the training, the participants of the Russian and Belarusian military will continue working on joint planning of using the regional group of troops from the Belarusian Republic and the Russian Federation in order to ensure the military security of the Union State," the ministry's statement said.
The drills will continue into Friday.
More joint drills are to come next week, the Belarusian Defense Ministry added. On April 14-16, Russian paratroopers will take part in military exercises in the Belarusian Brestsky Range.
The two neighbor countries enjoy one of the strongest ties in the post-Soviet space. In 2000, they established a supranational entity called the Union State.
According to the Russian defense chief, the Russian and Belarusian military will reinforce defenses on the Union State's common border with a series of "practical actions and events." One of such events is an upcoming joint exercise code-named Shield of the Union, scheduled for September 2015.
The Ukraine crisis badly strained Russia's relations with Western and Eastern Europe. The US-led NATO military bloc has subsequently stepped up its presence on the Russian border, specifically in Poland and the former Soviet Baltic states of Latvia, Lithuania and Estonia.
