Belarusian President Alexander Lukashenko said his country is on high alert for terrorism due to tensions on its borders.
Mr. Lukashenko linked the decision to his declaration on Monday that he had ordered Belarusian troops to deploy along Belarus’s southern border with Ukraine alongside Russian forces.
“In connection with the escalation of tension, a regime of heightened terrorist danger has been introduced,” Mr Lukashenko said in a Russian TV interview.
“Therefore we began a procedure with the Union group of forces, the basis of which, as I already said, is the Belarusian army, which will be supplemented by units from the Russian Federation. Everything is going according to plan.”
Belarus is allied with Moscow but wedged between Russia, Ukraine, and three NATO countries.
Belarus allowed Russia to use its territory as one of the launchpads for its 24 February invasion.
Its latest troop movements have raised concern in Kyiv and the West that Mr Lukashenko may be about to commit his army to support Russia’s faltering war effort.
Political analysts say that is an unappealing option for him but that he may not be in a position to refuse if Russian President Vladimir Putin demands it.
Belarus depends on Russia politically and economically, and Mr Putin’s support helped Mr Lukashenko survive mass pro-democracy protests in 2020.
Mr Lukashenko crushed the demonstrations and all leading opposition figures have been jailed or forced to flee abroad.