Russia's army chief Valery Gerasimov visited Moscow's troops in Ukraine and said the Kremlin's forces seized a dozen eastern villages in February, the defense ministry said Sunday.
Gerasimov visit comes days before US-mediated talks with Kyiv in Geneva on ending almost four years of war and ahead of the fourth anniversary of Moscow's full-scale offensive against Ukraine.
"In two weeks of February, despite severe winter conditions, combined forces and military units of the joint task force liberated 12 settlements," Gerasimov said.
AFP could not independently verify these claims.
The pace of Moscow's advance picked up in Autumn, but Russia has not reached its goal to seize the Donetsk region in four years of war.
Russia demands that Kyiv withdraw from the Donetsk region for any deal to end the conflict -- terms unacceptable to Ukraine.
Gerasimov said Moscow's troops were moving in the direction of Sloviansk -- an industrial hub that briefly fell to pro-Russian separatists in 2014 and which has been under frequent Russian attack.
Moscow's forces are around 15 kilometers (nine miles) from the city.
Moscow claims the Donetsk, Lugansk, Zaporizhzhia and Kherson regions as its own.
But it has also advanced into other Ukrainian regions.
Gerasimov said Russia was "expanding a security zone" in border areas in the northeastern Sumy and Kharkiv region, where it controls pockets of territory.
The army chief also said he would discuss with officers "further actions in the Dnipropetrovsk direction."
Russian forces crossed into the Dnipropetrovsk region last summer in their push westwards -- but the Kremlin has never laid an official claim on the region.
Russian leader Vladimir Putin has repeatedly said Moscow is intent on seizing the whole of the Donetsk region by force if diplomacy fails.
