Ukraine Is Taking Back Ground in a Key Region as Russia’s Long Offensive Continues to Stall
Ukraine is clawing back territory in the Donbas and disrupting Russia’s attempt to encircle some of Kyiv’s most important remaining strongholds in the east, challenging President Vladimir Putin’s repeated assertions that Moscow’s conquest of the region is inevitable.
A New York Times report showed that the months-long Ukrainian counteroffensive in the northern Donbas, dubbed Operation Vivaldi, has recaptured dozens of square miles and forced Russia to contend with a Ukrainian advance just as Moscow was trying to tighten its grip around the remaining Ukrainian-held cities in the region.
The gains remain small compared with the vast amount of Ukrainian territory occupied by Russia. But they are significant because they have interrupted Moscow’s plans for a wider encirclement of Ukraine’s heavily fortified Donbas cities at a moment when Russia had been portraying further advances as unavoidable.
The Institute for the Study of War has assessed that Operation Vivaldi disrupted Russian plans to envelop Ukraine’s so-called “fortress belt,” which includes the strategically important cities of Sloviansk, Kramatorsk and Kostiantynivka.
More broadly, Russia’s territorial gains across Ukraine have slowed sharply in 2026. Finland-based research group Black Bird Group found that September was Russia’s worst month for net territorial gains inside Ukraine since June 2023.
Over the month of September, the Russian net gains were negative 190 km2. This marks the greatest monthly net territorial loss for Russia in our dataset since the June of 2023.
(1/12) pic.twitter.com/SKRSWbIrzo
— Black Bird Group (@Black_BirdGroup) October 3, 2026
However, Russia’s Defense Ministry said in September that its forces had captured more than 2,000 square miles of territory. Even some ultranationalist Russian military bloggers have questioned the progress of the offensive and expressed concern that Moscow’s effort to surround the Donbas fortress cities is faltering.
Operation Vivaldi takes its name from Antonio Vivaldi’s “The Four Seasons,” with Ukraine describing different stages of the campaign as “seasons.” Before attacking, Ukrainian forces spent months preparing the battlefield.
Ukraine also targeted experienced Russian drone operators, using signals intelligence to locate their positions. Where Russian forces relied on fiber-optic drones, Ukrainian scouts tracked the physical cables back toward launch sites.
Mine warfare played another important role. Ukrainian forces used robotic systems to clear routes through minefields while deploying drones to scatter mines along Russian supply routes.
Once those conditions were in place, Ukrainian forces attacked. Ground robots equipped with explosives and machine guns were used behind Russian positions, while armored vehicles advanced along sections of the front to clear defensive positions.
President Volodymyr Zelensky has said more than 5,000 Russian troops were killed during the operation and another 250 captured. Those figures have not been independently verified, and Ukraine does not publicly disclose comprehensive casualty figures for its own forces.
Farther south, however, Russia continues to exert enormous pressure. After breaking through Ukrainian defenses around Pokrovsk in 2025, Russian forces pushed westward and threatened Ukrainian access to important supply routes. Moscow captured Pokrovsk early this year and continued advancing north, potentially opening another route toward the fortress cities.
Ukraine has increasingly relied on drones, robotic ground vehicles and its Delta digital battlefield management system to identify Russian assault groups and coordinate attacks. Russia, meanwhile, has leaned heavily on infiltration tactics. Individual soldiers or small teams attempt to cross miles-wide areas saturated with reconnaissance and attack drones before gathering behind Ukrainian defenses.
Putin has insisted that full Russian control of the Donbas, whether achieved militarily or through Ukrainian concessions, is a nonnegotiable condition for ending the war. Kyiv has rejected proposals that would require it to surrender territory Russia has failed to capture on the battlefield.
