Ukraine’s Lyman/Vivaldi Offensive Concludes With Solid Terrain Gains, Russian Losses

Operation Vivaldi was a months-long Ukrainian offensive in the Lyman sector. Brig. Gen. Andriy Biletsky said the 3rd Corps had completed its fourth and final phase. The operation mattered because it showed Ukrainian forces could attack while remaining outnumbered elsewhere.

During the campaign, Ukrainian troops used infantry, vehicles, and drone swarms to penetrate Russian positions, cut supply routes, and isolate defenders. Biletsky said the final phase liberated Zelena Dolyna, Lypove, and Kolodiazi. He described the overall operation as returning more than 16 settlements and 277 square kilometers to Ukrainian control.

Biletsky claimed at least 8,000 Russian troops were lost during Vivaldi. The Kyiv Post reported that internal unit feeds, battle reports, OSINT trackers, and independent analysts broadly supported the battlefield movement claims. Russia’s Defense Ministry disputed the picture, insisting its forces held ground or advanced. Biletsky hinted at possible follow-up operations.

The overall figures describe the scale Ukrainian commanders attributed to Operation Vivaldi. Biletsky said 3rd Corps forces reclaimed more than 277 square kilometers and returned more than 16 towns and villages to Ukrainian control. He also claimed at least 8,000 Russian troop losses.

The operation’s phases produced different reported totals. By September 28, Biletsky said Ukrainian forces had liberated 176 square kilometers, retaken five villages, and caused about 2,000 Russian casualties. On Wednesday, he said the fourth phase added 101 square kilometers and more than 3,000 casualties, while naming three newly liberated villages.

These numbers remain claims rather than independently verified casualty totals. The article notes that neither Russia nor Ukraine publishes actual casualty counts. However, Kyiv Post reviews of internal unit information, battle reports, OSINT trackers, and independent analysis found battlefield lines broadly consistent with the territorial claims. The ISW separately credited Ukrainian troops with nearly 300 square kilometers.

The article places the Lyman sector east and northeast of Lyman, in the wider Donetsk battlefield. It describes Ukrainian operations against Russian positions there and links the area directly to the defense of Slovyansk and Kramatorsk. The sector therefore mattered beyond the villages changing hands.

The nearby Slovyansk-Kramatorsk highway is described as logistically critical. Biletsky said Ukrainian gains pushed Russian forces away from the route. That distance helped ensure defenses in Slovyansk and Kramatorsk would remain well supplied. The article identifies both cities as Russian conquest objectives named by Vladimir Putin.

The reported situation also formed part of a wider Ukrainian effort. A parallel offensive farther south used similar drone and infiltrating-infantry tactics east of Slovyansk and Kramatorsk. Together, the operations produced slightly greater Ukrainian aggregate terrain gains in September 2026 than Russian gains, the first such result since June 2025.

The immediate consequence is improved access to supplies for Ukrainian defenders in Slovyansk and Kramatorsk. Biletsky said Russian forces had been pushed away from the Slovyansk-Kramatorsk highway, which the article calls logistically critical. The route therefore became less exposed to nearby Russian pressure.

The mechanism is straightforward: when attacking forces are farther from a supply route, they have less direct influence over movement along it. Ukrainian commanders said this allowed defenses in both cities to remain well supplied. The article connects that result to the cities’ importance as Russian objectives named by Vladimir Putin.

This did not end the fighting. Ukraine’s Slovyansk-Kramatorsk counter-offensive was still ongoing, and a parallel Ukrainian offensive continued farther south. Biletsky also hinted at another operation by referring to “Wagner and Bach.” Meanwhile, Russia’s Defense Ministry denied the reported setbacks, while Russian milbloggers described continuing pressure.

The operation used several battlefield tools as one system rather than separately. Mounted infantry brought mobility, while dismounted troops moved into or around Russian positions. Drone swarms supported the assault and helped Ukrainian forces pressure defenders during the advance.

According to Biletsky, troops first infiltrated Russian positions. They then cut defenders off from supplies and isolated them before systematically clearing the positions. The article also reports that drone strikes caused many Russian casualties and prevented troops from digging in. Speed was central because Russian commanders had little time to react.

This method helped an outnumbered force create local advantages. Biletsky said Ukrainian troops did not give Russian forces time to replace losses or construct a viable defense. Independent observers and Russian milbloggers described similar pressure from Ukrainian drones and infantry. The article does not separately detail a reconnaissance chain, but it does identify drones as central to infiltration, attacks, and battlefield disruption.

Ukrainian and Russian casualty claims differ because the two sides present conflicting accounts of the battlefield, while neither government publishes its actual casualty totals. Ukraine reported thousands of Russian losses during Vivaldi. Russia’s Defense Ministry instead insisted that Russian forces were holding ground or advancing.

Independent observers test these narratives against other evidence. The Kyiv Post reviewed internal 3rd Corps information feeds, battle reports, and OSINT trackers. The US-based Institute for the Study of War assessed the campaign and credited Ukrainian troops with reclaiming close to 300 square kilometers. Russian milbloggers also described Ukrainian advances and pressure.

This process can support or challenge claims about territory and battlefield conditions, but it does not create a definitive casualty count. The article says internal Ukrainian reports recorded accumulating Russian casualties, mostly from drone strikes. It also notes that Kyiv Post’s review found battle lines generally consistent with Biletsky’s territorial statements, while casualty figures remained unconfirmed.

Modern combat does not depend only on the number of soldiers. A smaller force can sometimes gain an advantage by moving quickly, using drones, and attacking weak points rather than confronting a larger force directly. Biletsky called this an example of asymmetric tactics working against outnumbered forces.

In Vivaldi, Ukrainian infantry infiltrated Russian positions while drone swarms supported attacks. Troops cut supply links and isolated defenders before clearing their positions. Biletsky said speed prevented Russian forces from replacing losses or constructing a viable defense. Russian milblogger Mikhail Zvinchuk likewise reported that drones stopped Russian troops from digging in.

The article presents this as an operational success, not proof that larger forces are always defeated. Ukraine still faced Russian numerical strength, and the fighting continued in the Donetsk region. The reported gains suggest that mobility, battlefield information, drone pressure, and disruption can let smaller units win local contests while maintaining defense elsewhere.