The ministry did not specify how long Russian troops in Belarus – estimated by NATO at 30,000 men – could now remain in the country, located in northern Ukraine.
The decision to extend was taken due to increased military activity near the borders of Russia and Belarus and an escalation of the situation in Ukraine’s eastern region of Donbass, the Belarusian ministry said in a statement.
The next stage would concern areas of defense that had not been fully covered by previous stages of training, Belarusian Defense Minister Viktor Khrenin said.
“In general, its purpose will remain unchanged – it is designed to ensure an adequate response and de-escalation of military preparations by the bad guys near our common borders,” Khrenin said.
There was no immediate comment from Russia.
The buildup of Russian forces around Ukraine, currently estimated by the West at more than 150,000 in the north, east and south, has prompted NATO to send reinforcements to Eastern Europe.
Moscow, which denies preparing to invade Ukraine, seized on it to argue that it is the United States and its allies who are fueling tensions.
Demonstrating the close alliance between Moscow and Minsk, Belarusian President Alexander Lukashenko sat with Vladimir Putin in a “situation center” on Saturday as the Russian president observed strategic nuclear exercises involving the launch of hypersonic and cruise missiles.