The leader of the Ukrainian army on Sunday admitted that Kyiv's position on the battlefield has worsened after Russian forces captured another village in the east, pressing their advantage in manpower and ammunition.

Russia's troops are advancing in the eastern Donetsk region as Kyiv awaits the arrival of much-needed U.S. weapons that it hopes will stabilize the fragile front lines.

"The situation at the front has worsened," Ukrainian commander-in-chief Oleksandr Syrsky said in a Facebook post.