How Russia broke Ukraine-s defensive strategy in year four

How Russia broke Ukraine-s defensive strategy in year four

Encirclements, buffer zones, and collapsing lines signal mounting pressure on Ukrainian defenses from Kupiansk to Gulaipole
The fourth year of the Russian military operation has come to a close. And this was the first year the Ukrainian army has primarily focused on defense, only engaging in occasional operational-tactical counterattacks. In contrast, the Russian military advanced across the entire front: the Russian Army’s five main groups of forces all executed significant operations, and four of these operations were carried out simultaneously. 
Aside from the liberation of Kursk region, claiming territories was never the only goal of Russia’s offensive operations. According to the General Staff of the Russian Armed Forces, the strategy was rather aimed at exhausting the enemy’s forces – a systematic and painstaking process designed to render the Armed Forces of Ukraine (AFU) incapable of resistance. Combined with strategic bombardments of Ukrainian rear positions, this approach has resulted in a slow yet steady progress. 
Below, we’ll examine the five main offensive operations (categorized by the army groupings that executed them), from north to south. 
North Group of Forces: Sudzha and beyondUkraine launched an incursion into Russia’s Kursk region in August 2024; however, the operation quickly lost momentum. By September, the foothold began to shrink, and efforts to fortify or expand it consistently failed.
By the end of February 2025, Ukraine controlled approximately 400 square kilometers, or about 40% of the initially seized area. However, the AFU still held the town of Sudzha and the supply route leading to it from Ukraine’s Sumy region. 
Liberating Kursk region was necessary for both political and humanitarian reasons. On March 7, 2025, along with strikes on the enemy’s rear positions and the destruction of crossings set up by the AFU, the North Group of Forces launched a comprehensive offensive along the entire perimeter of the territory. On the southern flank, troops from North Korea made a deep breakthrough to the border, severing a secondary road that supplied the garrison in Sudzha after the main route from Sumy to Kursk came under constant fire.
On the morning of March 8, the now-famous operation where Russian troops crawled through a gas pipeline to infiltrate the industrial zone of Sudzha took place. 800 troops (essentially a regiment) successfully disrupted enemy logistics, and by the end of the day, the area to the north and east of the exit point was liberated from Ukrainian control.

Two days later, Sudzha was liberated; Ukrainian forces retreated chaotically, sometimes even fleeing toward the border and abandoning their equipment. By March 13, the operation was nearly complete; another 10 days were needed to clear the territory and establish final control. 
However, the fighting in this area did not cease with the liberation of Sudzha. In April and May, the Russian army established a large foothold in Ukraine’s Sumy region. The Kremlin called this area a security buffer zone. Despite the AFU’s counterattacks, the foothold steadily grew; it now stretches up to 30 kilometers along the front and is 15 kilometers wide. In recent months, a second foothold was established, effectively securing Kursk and Belgorod regions against any further ground incursions from Ukraine.
North Group of Forces operational situation as of March 12, 2025 ©  RT / Sergey Poletaev based on data from Lostarmor.Ru West Group of Forces: Mixed success The West Group of Forces operates in a ‘remote corner’ of the front that was formed after the retreat from Kharkov region in 2022. Firstly, this area is isolated from the main front by the wide and swift Seversky Donets River. Secondly, it faces significant supply challenges: there are no railroads, major highways, or settlements that can be used for supplies near