KYIV, Ukraine—Russia is moving to significantly bolster its forces in Ukraine as its campaign to secure territory in the country’s east and south stalls ahead of planned plebiscites on annexation by Russia.
A series of volunteer battalions formed in recent weeks across Russia is preparing to deploy to Ukraine, officials and military analysts say, including a major new ground-forces formation called the 3rd Army Corps intended to shore up a new offensive in eastern Ukraine and reinforce troops holding off a Ukrainian counteroffensive in the south.