ISW: Ukraine's Operation Vivaldi creating "cascading effect" across Donetsk front, stalling Russian advances
The Institute for the Study of War reported that Ukraine's Operation Vivaldi in the Lyman area is producing a "cascading effect" on neighboring sectors in Donetsk Oblast, slowing Russian attempts to advance toward Slovyansk, Kramatorsk, Borova, and Kupiansk-Vuzlovyi. On 14 October, the Third Army Corps announced the liberation of three more settlements and 101 additional square kilometers in the fourth stage of the operation.
Key points
- ISW assesses Operation Vivaldi is creating a "cascading effect" in sectors north and south of the Lyman district in Donetsk Oblast.
- On 14 October, the Third Army Corps announced liberation of Zelena Dolyna, Lypove, and Kolodyazi.
- Corps commander Brigadier General Andriy Biletsky said 101 square kilometers were liberated in the operation's fourth stage.
- Since the start of Operation Vivaldi, Ukrainian forces have de-occupied 16 settlements and 277 square kilometers of territory, according to the Third Army Corps.
- ISW assessed that Ukrainian counterattacks east of Slovyansk combined with the defeat of Russian forces north of the Siverskyi Donets river could ultimately halt the Russian advance on Slovyansk from the east.
- Russian offensive operations on 13 and 14 October in the Kupiansk direction, north of Kharkiv Oblast, and toward Borova made no progress.
- ISW refuted information circulating about an alleged encirclement of Ukrainian forces in Kharkiv Oblast.
Why it matters
Operation Vivaldi is undermining Russian offensive plans across a wide front, according to ISW, from the Slovyansk-Kramatorsk agglomeration to the Kupiansk direction. The operation has produced concrete territorial gains — three additional settlements and 101 square kilometers in its latest stage, with 16 settlements and 277 square kilometers since the start — and ISW says the cumulative effect has stalled Russian advances to the point that Russian forces sometimes now lose more territory than they capture.
What happened
On 14 October, Ukraine's Third Army Corps announced the liberation of three more settlements in Donetsk Oblast — Zelena Dolyna, Lypove, and Kolodyazi — as part of Operation Vivaldi. Corps commander Brigadier General Andriy Biletsky stated in a released video that 101 square kilometers of additional territory had been liberated in the fourth stage of the operation, and that the operation's key success factor was speed. According to the Third Army Corps, since the start of Operation Vivaldi Ukrainian forces have de-occupied 16 settlements and 277 square kilometers.
Biletsky said Ukrainian forces prevented the enemy from outflanking the Slovyansk-Kramatorsk agglomeration and encircling it, and protected the Kharkiv-Slovyansk highway. He added that Ukrainian forces disrupted the advance of Russia's "West" (Zapad) grouping and forced it to redeploy parts of the 1st Tank Army, weakening pressure on Kupiansk-Vuzlovyi.
The Institute for the Study of War reported that Operation Vivaldi is producing a "cascading effect" in sectors directly north and south of the Lyman district, slowing Russian attempts to advance toward Slovyansk and Kramatorsk from the east, as well as operations north of Lyman toward Borova. On 13 and 14 October, Russian forces made no advances in the Kupiansk direction, in northern Kharkiv Oblast, near Lyman, near Borova, or east of Slovyansk near Kryva Luka, Mykolaivka, Pyskunivka, and Kalenyky. ISW also refuted information about an alleged encirclement of Ukrainian forces in Kharkiv Oblast. ISW previously noted that the tempo of Russian advances dropped significantly in March 2026 and has remained "low" since, and that Russia sometimes now loses more territory than it captures.
Background
Operation Vivaldi is being conducted by Ukraine's Third Army Corps in the Lyman area of Donetsk Oblast, with the stated aim of disrupting Russian plans to encircle the Slovyansk-Kramatorsk agglomeration and cut the Kharkiv-Slovyansk highway. ISW has previously noted that the pace of Russian advances dropped significantly in March 2026 and has remained low since, and has refuted claims circulating about an alleged encirclement of Ukrainian forces in Kharkiv Oblast.