Operation “Vivaldi” by the Ukrainian Armed Forces north of Sloviansk shows why neither Russia nor Ukraine has managed to quickly change the course of the war. The offensive has produced an operational effect for Kyiv, but the advance was limited to 10–20 kilometers after months of preparation. The main method on both sides remains the infiltration of small assault groups, rather than large-scale mechanized maneuver.
How Operation “Vivaldi” Was Prepared
Ukrainian servicemen who took part in the operation claim that they used a new tactic, but have not disclosed details so they can exploit weaknesses in the Russian army again. According to former commander of the 3rd Army Corps Andriy Biletsky, preparations began as early as May.
Initially, Ukrainian forces focused their efforts on disrupting the supply of the auxiliary units of Russia’s 20th Combined Arms Army, deployed north of Lyman. These units include drone operators and electronic warfare teams—elements that provide reconnaissance and protection for Russian positions.
After this system had been weakened over an extended period, Ukrainian assault groups advanced from the west, north and south. They attacked Russian positions around Novoselivka, Shandryholove, Kolodiazi and Nove. As a result, the forward units of the 20th Army lost a significant portion of their reconnaissance and fire-support assets and abandoned nearly all positions west of the Chorna Zherebets River.
An American volunteer from the 3rd Army Corps compared the preparation to “an avalanche in the mountains”—a slow process in which changes accumulate before the mass collapses. At the Chorna Zherebets, however, the Ukrainian advance was halted by Russian artillery fire and drone strikes from the eastern bank.
Operational Success, but No Breakthrough
The tactical result appears limited if measured by the area of territory captured or the depth of the advance. Its operational significance, however, is greater, since after the 20th Army’s withdrawal behind the Chorna Zherebets, the northern flank of the 25th Army remains more vulnerable. It continues to hold positions around Lyman and provides cover for Russia’s “South” grouping, which is advancing toward Sloviansk along the southern bank of the Siverskyi Donets.
Ukrainian military sources claim that the operation thwarted a larger Russian plan to encircle Ukrainian forces in the Kramatorsk and Sloviansk area. This scenario would have involved capturing the area around Sviatohirsk, forcing a river more than 100 meters wide and cutting the road between Sloviansk and Izium. An analysis of the deployment and actions of Russian units, however, points to a more limited task for the 20th Army—reaching the Siverskyi Donets and covering the flank of the 25th Army.
Why the Front Remains Positional
Drones and precision-guided weapons have gradually made the front and the immediate rear more transparent. Any concentration of armored vehicles, artillery and infantry can be detected and struck. As a result, large formations find it difficult to move, while the main role increasingly falls to small groups that move covertly in bad weather or at dusk.
In 2025 and the first half of 2026, assault groups have shrunk from 10–15 people to pairs and individual fighters. They can infiltrate between positions, but have difficulty holding what they capture without supplies and reinforcements. Fighters from both sides often find themselves on the same street without engaging in direct small-arms combat.
Russia has also used a similar approach. After months of preparation, Russian forces captured Dobropillia and reached the road toward Kramatorsk, advancing 20–25 kilometers since the beginning of the year. Thus, both armies can achieve local successes, but the price is prolonged preparation, dispersed forces and significant losses. The struggle for Kramatorsk and Sloviansk remains central to Russian and Ukrainian military planning.
Sources: meduza.io