Russian forces have taken control of the strategic city of Kupyansk in the Kharkov region in eastern Ukraine, Chief of the General Staff of the Russian Armed Forces Valery Gerasimov said Thursday.

Units of the Zapad (West) group have seized the city of Kupyansk and are continuing to destroy Ukrainian forces encircled on the left bank of the Oskol River, Gerasimov reported to Russian President Vladimir Putin.

Gerasimov said that advances are underway in Krasnoarmeysk, another strategic city in eastern Ukraine, adding that over 75 percent of the city's territory is now under Russian control.

Russian troops have taken 13 villages since the beginning of November -- six in the Dnipropetrovsk region and seven in the Zaporizhzhia region, he said.

Kupyansk is a key logistics hub and defense stronghold for Ukrainian forces in the Kharkov region. Russia previously controlled the city from February to September 2022, during which time it served as the region's administrative center.