ISW: Russia’s Huliaipole breakthrough came from months of preparation, not sudden Ukrainian collapse (MAP)

Russian troops broke through Ukrainian lines near Huliaipole after months of force buildup and large-scale redeployments, according to a new assessment by the Institute for the Study of War (ISW). 

The breakthrough near Huliaipole comes as Russia has been pressing in several sectors and Ukraine tries to hold long defensive lines with limited reserves. Moscow has been shifting units between regions to find weak points, while Kyiv faces the challenge of stopping deeper advances during a difficult phase of the war.

Russia massed force equal to Pokrovsk grouping

ISW says Moscow massed a grouping of units roughly equal in size to the force attacking in the Pokrovsk-Dobropillia sector, then pushed it forward in mid-November. 

The majority of frontline fighting in recent months has been concentrated around Pokrovsk in Donetsk Oblast, which has been Ukraine’s primary defensive focus, with both sides committing large forces and resources to hold or advance positions there.

The think tank cites Ukrainian analyst Kostyantyn Mashovets, who said Russia’s Eastern Grouping of Forces in the area now matches or exceeds the manpower level of the Central Grouping fighting further north. 

Ukrainian officials previously estimated that Russia deployed up to 220,000 troops to the Pokrovsk direction, underscoring the scale of Moscow’s effort around Huliaipole.

Moscow pulled units from Sumy, across the front

ISW notes that Russia pulled in airborne units from Sumy, motorized rifle formations from the Central District, and additional brigades from across the front to build strength in the area.

Mashovets said the added units boosted the Russian forces’ ability to punch through Ukrainian lines to a depth of around 17 kilometers, cross the Yanchur River near Uspenivka, and reach the northern outskirts of Huliaipole. He warned that Russia may try to bring in more elements to widen the breach.

ISW argues that the breakthrough reflects months of concentrated preparation rather than any sudden collapse of Ukrainian defenses, despite claims by Moscow. It says Russia will likely need even more troops - and a shift of focus from other parts of the front - to turn the advance into a wider success.

River crossings may determine next phase

The next phase may depend on whether Russian units can cross the Haichur River, which runs through Huliaipole. ISW says crossing points near Danylivka could allow Russian troops to pressure Ukrainian forces from the north and northwest and potentially target key supply routes into both Huliaipole and Orikhiv.

Ukrainian counterattacks slow advance

Ukrainian forces are still holding lines northeast of the town. ISW notes that counterattacks have pushed elements of Russia’s 36th Army back near Sosnivka and helped Ukraine keep a foothold on the Vorona-Vovcha river line. 

Defenses around Oleksandrivka are also holding, which could slow any Russian attempt to push toward the Haichur River and complete an encirclement.