Russia’s Slow Advance Raises the Stakes in Donbas

War by Infiltration

Russian troops increasingly try to penetrate Ukrainian positions or built-up areas in small groups rather than relying solely on larger assault formations. Some are detected and hit by drones or small arms, while others manage to establish positions between or behind Ukrainian lines, widening the contested gray zone.

The method itself is not entirely new. Small assault groups were also widely used during the battle for Bakhmut in 2023. On today’s increasingly drone-saturated battlefield, however, dispersed infiltration has become particularly important because larger concentrations of troops are far easier to detect and strike.

The aim is often not an immediate breakthrough, but to identify weak points, disrupt Ukrainian defenses and gradually establish positions from which further troops can move forward. Ukrainian commanders interviewed by Business Insider described Russian soldiers advancing individually or in very small groups, with others following whenever one succeeds in reaching a designated position.

The Institute for the Study of War (ISW) assesses that capturing the remainder of the Donetsk region remains a key Russian objective in eastern Ukraine, alongside further advances toward the Dnipropetrovsk region.

Progress remains slow and uneven. ISW recorded no confirmed Russian advances on the Sloviansk, Kostiantynivka-Druzhkivka or Pokrovsk axes on 2 and 3 September, while Ukrainian forces were also conducting localized counterattacks.

Over the course of August, however, Russia did continue to gain ground in the Donetsk region. Its forces seized about 73 sq km. ISW assessed that they advanced or infiltrated into a total of about 104 sq km during the month, although the larger figure includes contested infiltration zones and does not mean that all of that territory was consolidated or fully occupied.

That is far below Russian President Vladimir Putin’s claim on 1 September that Russian forces had captured 270 sq km and 15 settlements in the Donetsk region during August. ISW said the available open-source evidence did not support his assertion.

Ukraine still controls just under one-fifth of the Donetsk region, an area of roughly 5,000 sq km. A European intelligence assessment cited by Business Insider suggested that Russian troops could reach the outskirts of Kramatorsk and Sloviansk by early 2027.

Yet that forecast is far from certain. Military analyst Franz-Stefan Gady told the publication that, at the current rate of advance, Russia would not capture the whole of the Donetsk region until the early 2030s. He said Russian forces might reach Kramatorsk and Sloviansk in spring or summer 2027 only if Moscow carried out another mobilization capable of sustaining or increasing the current pace.

The Donbas Fortress Belt

The importance of the remaining Ukrainian-held part of the Donetsk region extends well beyond the territory itself. Ukraine has spent more than a decade fortifying the chain of cities running through Sloviansk, Kramatorsk, Druzhkivka and Kostiantynivka.

The roughly 50-km defensive belt forms the backbone of Ukraine’s positions in the region. Sloviansk and Kramatorsk serve as major logistics centers in its northern half, while Druzhkivka and Kostiantynivka anchor the south.

Surrendering the area would therefore have consequences beyond the immediate loss of land. Russian forces would move considerably farther west and gain more favorable starting positions for any future offensive toward the Kharkiv or Dnipropetrovsk regions.

That military significance also helps explain why the Donbas has become one of the main obstacles to a peace agreement.

In April 2025, the Kremlin demanded that Ukrainian troops withdraw from all four Ukrainian regions that Moscow claims to have annexed: Donetsk, Luhansk, Zaporizhzhia and Kherson.

Russia maintained those territorial demands in 2026. In May, Peskov again said that Ukrainian forces would have to leave the Donbas and other territories claimed by Moscow before meaningful peace talks could begin.

For Kyiv, such a withdrawal would mean abandoning fortified positions that Russian troops have so far been unable to capture militarily.

It would also place more civilians under Russian occupation. UN human rights monitors reported in March that Russia had imposed discriminatory measures on a widespread and systematic basis in occupied Ukrainian territory. These included forced transfers and deportations, pressure to obtain Russian citizenship and restrictions on fundamental freedoms enforced through threats, detention, torture and ill-treatment.

Russia has also continued efforts to integrate occupied Ukrainian territory into its political, legal and cultural system.

At the same time, years of war have increased pressure for a negotiated settlement. Ukrainian public opinion, however, remains resistant to surrendering the Donbas outright. A survey conducted by the Kyiv International Institute of Sociology between 20 July and 3 August found that 60% of respondents considered it categorically unacceptable for Ukraine to withdraw from the Donbas in return for US and European security guarantees. Another 33% said they were prepared to accept such a concession, although most described it as a difficult condition.

Preparing for a Long War

Francis Farrell, a journalist with the Kyiv Independent who has covered the war since 2022, argued in an August analysis that many of the restraints that had prevented the conflict from becoming a total war were disappearing.

Neither side currently appears close to a decisive battlefield victory. Instead, manpower, weapons, industrial capacity and the ability to absorb losses over time are becoming increasingly important.

Kyiv is also changing its command structure in the Donetsk region. On 26 August, President Volodymyr Zelensky announced that two restructured force groupings would reinforce Ukrainian positions there following proposals from Commander-in-Chief Mykhailo Drapatyi.

They will be led by Andriy Biletsky, commander of the Third Army Corps and founder of the Third Separate Assault Brigade, and Denys Prokopenko, commander of the National Guard’s First Corps Azov.

Before the restructuring, Biletsky’s forces were responsible for more than a tenth of the entire front line. His corps has also been at the forefront of efforts to integrate unmanned ground vehicles, drones and other automated systems into combat operations.

Biletsky told Reuters in May that his units aimed to use robotic and unmanned systems to replace significant portions of infantry roles, with a target of 30% by 2027. The objective is to conserve troops and reduce their exposure on the battlefield.

Diplomatic efforts are continuing in parallel. US envoys Steve Witkoff and Jared Kushner are expected to visit Moscow and Kyiv over the weekend of 5–6 September as part of Washington’s efforts to broker an agreement between Russia and Ukraine.

As of 4 September, however, the trip had not been finalized. Washington was still seeking security commitments from both sides before the envoys could travel, Reuters reported.

Witkoff and Kushner last visited Moscow in January, when they held four hours of late-night talks with Putin in the Kremlin.

For now, the military and diplomatic tracks remain difficult to reconcile. Russia continues to press toward one of Ukraine’s most important defensive zones, but its gains remain slow and costly. Kyiv, meanwhile, is unwilling to surrender fortifications that Russian forces have been unable to take on the battlefield – precisely the territory Moscow continues to demand as part of any settlement.