Putin announced the appointment as part of what he called an “optimization” of the military structure, roughly midway through the fifth year of the war in Ukraine. Until now, Lyamin served as chief of staff for the “Center” group of forces, part of the Russian military fighting in Ukraine. He is a graduate of an armored forces command academy and comes from a ground forces background. Putin described the “Center” group as a key part of Russia’s operations to seize the entire Donetsk region, one of Moscow’s top priorities in the war. He will be replaced by Andrei Ivanaev, who until now commanded the “East” group of forces.