Following the advance of Russian troops into the Ukrainian border region of Kharkiv, Ukrainian Commander-in-Chief Oleksandr Syrskyi has described the situation there as "difficult."
"This week, the situation in the Kharkiv region has significantly worsened," Syrskyi 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 that 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."
Various sources reported that Russian troops launched an offensive in the early hours of Friday in the border area with the Ukrainian city of Kharkiv.
According to the Russian Ministry of Defence, a number of Ukrainian border villages near the town of Vovchansk were taken. On Sunday, Moscow reported the capture of four further villages.
Ukrainian President Volodymyr Zelensky, who has repeatedly called for more international help in the defence of his country, recently declared that stopping the Russian offensive in Kharkiv was now "objective number one."