Ukrainians Have Crossed the Siverskyi-Donets River In Force

Crossing the Siverskyi Donets with small teams of special forces was significant enough, because it underscored the degree to which the Russians had lost control not just of the Lyman salient, but of their ability to defend their fallback positions.

By crossing the river in force with larger units in several locations, the Ukrainians are putting additional pressure on the Russians to try to defend what they have left in that sector, as opposed to even thinking about offensive operations. JL 

Raj K reports in Medium:

The Ukrainian army has crossed a key natural barrier—the Siverskyi Donets River. The most important result of this advance is that Russian soldiers are now being pushed back behind the same natural barriers that took them months and heavy resources to cross. The first sign that the Russian defense line was breaking came from reports by Russian military bloggers who admitted that Russian soldiers have been driven out of Pyskunivka and had now taken defensive positions on the approaches to Kryva Luka. The Ukrainian soldiers are putting pressure on them by crossing the river from the direction of Ozerne as well as from the west. With Ukrainian control established on both banks of the river, the Russian army has been pushed into an extremely vulnerable and defensive position just before the arrival of winter.

On December 4, 2025, in an aggressive and confident statement from Moscow, Russian President Vladimir Putin claimed that Ukraine had only two options left — either it would voluntarily leave Donetsk, or the Russian army would use full force to take control of the entire area.

But in October 2026, the reality on the battlefield is the complete opposite of Putin’s claim. Instead of Donetsk falling, the Ukrainian Armed Forces have started strategically coordinated and highly aggressive counterattacks.

The Ukrainian army has crossed a key natural barrier—the Siverskyi Donets River.

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Donets River

According to recent assessments by strategic analysts and the Institute for the Study of War (ISW), Russia has suffered heavy tactical and territorial losses in the Donetsk sector.

The Ukrainian army is advancing rapidly to the east of Sloviansk and Kramatorsk.

The most important result of this advance is that Russian soldiers are now being pushed back behind the same natural barriers that took them months and heavy resources to cross.

The first sign that the Russian defense line was breaking came from reports by Russian military bloggers and open-source intelligence (OSINT) analysts.

The well-known Russian military Telegram channel ‘Rybar’ admitted that Russian soldiers have been driven out of the remains of the Pyskunivka settlement and have now taken defensive positions on the approaches to Kryva Luka.

The most important point in this account is that Ukrainian soldiers are also putting pressure on them by crossing the river from the direction of Ozerne as well as from the west.

From the point of view of military strategy, attacking from the direction of Ozerne clearly means that Ukraine has already established full control over Ozerne.

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On the other hand, on the opposite bank of the Siverskyi Donets River, the Ukrainian army has carried out an extremely precise pincer attack on the Kryva Luka settlement from the west and northwest.

This action is a direct strike on the foundation of that Russian salient (bulge) that Russian forces had been trying to build for months.

In the history of warfare, rivers have always been seen either as a formidable shield or as a deadly obstacle.

When an army crosses a river and sets foot on the opposite bank, the entire calculation changes for the attacking army.

Crossing a water barrier while remaining under the direct aim of artillery and drone surveillance is one of the most difficult military operations in modern warfare.

Now, Russia will not only have to recapture Kryva Luka to advance in Donetsk but will also have to take the risk of crossing the river under Ukrainian shelling.

According to tactical maps and geographical data, the average elevation of the Kryva Luka settlement is 102 meters, while its maximum elevation reaches up to 174 meters.

In modern warfare, the army that controls the heights gets a decisive advantage in clear surveillance of the battlefield, precise artillery coordination, and drone operations.

With Ukrainian control established on both banks of the river, the Russian army has been pushed into an extremely vulnerable and defensive position just before the arrival of winter, where its logistics supply lines are constantly within the range of Ukrainian attacks.

Sloviansk, Kramatorsk, Kostiantynivka, and Druzhkivka, located in the western part of the Donetsk region, are collectively called the ‘Fortress Belt.’

This urban and industrial area has been the main base of Ukraine’s defense system. The main objective of the Russian army was to break this belt and establish full control over the entire Donbas region.

After the collapse of their salient near Lyman, Russian forces changed the direction of their attack toward the south, and their main target became Mykolaivka.

Mykolaivka is tactically located to the east of Sloviansk, and because it sits on local heights, the Russian command wanted to make it a launchpad for an attack on Sloviansk.

But the Ukrainian defense command had already sensed this plan. Ukrainian soldiers prepared another pincer movement by launching simultaneous counterattacks from the northeast and southeast of Mykolaivka.

Military analysts see this sudden change on the Donetsk front as the effect of Ukraine’s much-discussed ‘Operation Vivaldi.’

Although the Ukrainian General Staff maintains strict operational secrecy and makes official information about campaigns public only after their successful completion, the results visible on the ground match the strategy of this broad campaign.

In the previous phases of Operation Vivaldi, the Ukrainian army had recaptured more than 176 square kilometers of important territory.

Recently, under its third phase, 51 square kilometers of territory and several settlements were liberated, during which reports of the surrender of a large number of Russian soldiers also emerged.

Ukraine’s ‘deep strike’ strategy has underpinned the success of this entire campaign.

Through new-generation long-range drones and precise artillery, the Ukrainian army has systematically destroyed Russian ammunition depots, command posts, electronic warfare stations, and drone bases located several kilometers behind the front line.

When soldiers on the front line lose contact with their logistics and command, their defensive walls start collapsing.

For the Russian leadership, Donetsk is not just a geographical area; it has become the final political symbol justifying this entire military campaign.

After the original objective of controlling the whole of Ukraine or changing the government in Kyiv failed in 2022, the Kremlin focused its entire narrative on the ‘liberation of Donbas.’ For Putin, this area has become the center of his prestige and domestic political stability.

Moscow’s diplomatic stance was based on the belief that the fall of Donetsk was inevitable. Putin’s main strategy has been to convince the international community and Western allies that Ukraine would not be able to save this area for much longer, so that in any potential peace talks Russia could set its terms from a strong and decisive position.

In 2026, the ratio of Russia’s territorial gains to the human cost it has paid is one of the most unbalanced ratios in military history.

So far in 2026, the Russian army has lost about 249,000 soldiers (dead and seriously wounded).

In exchange for this heavy human loss, Russia has been able to capture only a little more than 1,000 square kilometers of territory in the whole year.

This latest success of the Ukrainian army in Donetsk is not limited to taking back a few pieces of land. It has shaken the strategic balance of the entire battlefield.

The Ukrainian army has proved it cannot only fight an excellent defensive war, but also identify the enemy’s weaknesses and carry out large-scale aggressive counter-offensives.

By establishing control across the Siverskyi Donets River, gaining an advantage on strategic heights like Kryva Luka, and securing the Kramatorsk-Sloviansk Fortress Belt, the Ukrainian army has prepared a very strong base for the coming winter months.

In contrast, the Russian army is now stuck behind those natural obstacles, which will be extremely difficult to cross given its dwindling resources and falling morale.