The Ukrainian Armed Forces repelled the occupiers near Kupiansk and advanced in the Donbas, according to the ISW
Ukrainian forces are launching counterattacks on several sections of the front and have achieved isolated tactical successes in the Donbas. At the same time, Russian troops have not been able to make any confirmed advances near Kupiansk, Lyman, and in a number of other areas.
In the Kupiansk sector, Russian forces are continuing their offensive operations but have not made any confirmed advances.
Instead, Ukrainian forces have launched counterattacks against Russian outposts north and southeast of Kupiansk.
According to the ISW’s assessment, the situation for Russian troops in the immediate vicinity of the city is deteriorating. Ukrainian military officials report that the Russians are losing positions on the right bank of the Oskil River closer to Kupiansk. At the same time, Russian units are attempting to narrow the Ukrainian bridgehead southeast of the city.
One Ukrainian military official, quoted by the ISW, noted that Russian forces stepped up their activities in September after receiving reinforcements. However, over the past six months, they have not made any significant advances in this direction, while Ukrainian units have achieved isolated tactical successes.
Separately, Ukrainian forces are conducting a counteroffensive northwest of Lyman.
Andriy Biletsky, commander of the 3rd Army Corps of the Ukrainian Armed Forces, reported that as part of Operation “Vivaldi,” Ukrainian forces have liberated or cleared 85 square kilometers of territory.
According to him, Ukrainian forces have taken control of Seredne and have driven Russian troops out of Novoselivka, Yarova, Oleksandrivka, and the outskirts of Korov’yachyi Yar.
The ISW notes that Ukrainian forces likely advanced even further than officially reported.
In the Lyman area, Russian troops continued offensive operations on September 14–15, but made no new confirmed advances.
According to the ISW’s assessment, the Ukrainian counteroffensive has already complicated Russia’s plan to broadly encircle Ukraine’s fortified line of defense in the Donbas.
Ukrainian forces have also recently advanced southwest of Dobropillia, specifically in the Bilitske area.
The ISW notes that geolocated footage confirms the presence of Ukrainian forces in this area, despite claims by Russian sources of their own advances.
At the same time, the Russian army continues offensive operations near Kostiantynivka, Sloviansk, and in other parts of the Donbas. However, over the past 24 hours, the ISW has not recorded any confirmed advances by Russian troops in these directions.
This is stated in the Institute for the Study of War (ISW) report dated September 15, 2026.
Over the past 24 hours, units of the Unmanned Systems Forces struck or destroyed 1,393 enemy targets. Among them were three Russian naval vessels and 44 drone launch sites.
Over the past 24 hours, 278 combat engagements were recorded on the front lines. Russian troops carried out the most assaults in the Pokrovsk direction—Ukrainian defenders repelled 43 enemy attacks.
As of September 16, 2026, the Ukrainian military had eliminated 1,530 Russian occupiers over the past day. The Russian Federation’s total military losses increased by another 1,530 soldiers.
Since the start of the day on September 15, there have been 219 combat engagements on the front lines. Russian troops launched the most attacks in the Pokrovsk direction—there, Ukrainian forces repelled 38 assaults.
