Ukraine’s military chief has admitted his forces are facing a “difficult situation” in the northeastern region of Kharkiv, where thousands more people have fled their homes as Russian forces continue to advance, Paralel.Az reports citing Reuters.

“This week, the situation in the Kharkiv region has significantly worsened,” Oleksandr Syrskii wrote on Telegram on Sunday. “There are ongoing battles in the border areas along the state border with the Russian Federation.”

While admitting that the situation is “difficult” and Russian attackers had achieved “partial successes” in some areas, he said, “Ukrainian defence forces are doing everything they can to hold defensive lines and positions.”

The intense battles have forced at least one Ukrainian unit to withdraw, leaving behind more land to Russian forces across less defended settlements in the so-called contested “grey zone” along the Russian border.

By Sunday afternoon, the town of Vovchansk, among the largest in the northeast with a pre-war population of 17,000, emerged as a focal point in the battle.

Ukrainian President Volodymyr Zelenskyy said on Sunday that there were intense battles across parts of the region.

“Defensive battles and fierce fighting continue on a large part of our borderline,” Zelenskyy said, adding: “The idea behind the attacks in the Kharkiv region is to stretch our forces and undermine the moral and motivational basis of the Ukrainians’ ability to defend themselves.”