Belarusian leader Alexander Lukashenko has said the exercises would be held on Belarus' southern and western borders, however, Moscow denies any joint military plans.
Belarusian strongman Alexander Lukashenko has announced that his army will conduct military exercises next month with Russian forces and criticised what he said was NATO's growing presence in Europe.
Lukashenko said his plans for drills with Russia had been made in December in coordination with his ally, Russian President Vladimir Putin, but had not been announced at the time.
"We were planning to start exercises in February. Set an exact date and let us know, so we aren't blamed for massing some troops here out of the blue, as if we are preparing to go to war," the state Belta news agency quoted him as saying.
He said the drills would be dubbed "Determination of the Union 2022," and should focus on a scenario in which his country's military is forced to "resist forces coming from the West".
He said the exercises would be held on Belarus's southern and western borders but did not specify how many troops would be involved.
Russian military forces and hardware began arriving in Belarus on Monday, Belta quoted the secretary of the Belarusian Security Council, Alexander Volfovich, as saying.
Moscow denies any such plan but has used the standoff to campaign for security guarantees from the West, including a halt to NATO expansion and a formal veto on Ukraine, a former Soviet republic, ever joining the military alliance.
Russia has worried the West and Kyiv with a troop buildup near Ukraine's borders and a barrage of threatening rhetoric, stirring fears that it plans to invade.
The former Soviet republic of 9.5 million, which Moscow sees as a buffer state to the West, borders Ukraine to its south and NATO members Poland and Lithuania to its west.
Lukashenko, who has grown closer to the Kremlin as the West shunned him, accused Ukraine of building up troops near Belarus in comments circulated by the Defence Ministry.
He said Poland and the Baltics had more than 30,000 soldiers near Belarus' borders.
"These should be normal exercises to work out a certain plan in the confrontation with these forces: the west (the Baltics and Poland) and the south (Ukraine)," Belta quoted him as saying.
The Kremlin said separately that reports that Estonia was prepared to host up to 5,000 NATO troops showed Moscow was right to be worried.
"It's exactly things like that which prove we have grounds to be concerned and it proves we're not the reason for escalating tensions," Kremlin spokesman Dmitry Peskov said.