Russia Widens Sumy Push as Ukraine Torches Refineries

For Serbia, whose energy balance still leans on Russian oil and whose foreign policy is measured daily between Brussels and Moscow, what is unfolding this week in northern Ukraine is no distant dispatch from the front. Every burning refinery reshapes the logic of a market that a Belgrade filling station also depends on, and every shift of the Russian war machine toward the Sumy and Kharkiv regions tightens the space for Serbian diplomatic balancing. This week Moscow announced that it is expanding its offensive and intends to establish a so-called buffer zone along Ukraine’s northern border, even as its summer campaign loses momentum amid losses rarely acknowledged in the Russian capital.

Russian sources claim the zone already covers more than half of the border, but the reality on the ground looks far messier. Al Jazeera reported that the summer offensive has stalled and that in June alone nearly 40,000 Russian soldiers were put out of action, counting the dead and the wounded. It is a price that, by the same estimates, is stirring growing anxiety in Moscow, since the territorial gains remain modest against what has been spent.

A buffer zone as a political signal

Moscow uses the buffer-zone concept as a political rather than a purely military instrument. By casting northern Ukraine as a threat from which attacks supposedly originate, the Kremlin builds a justification for pushing the line of contact further and for prolonging the war indefinitely. Ukrainian President Volodymyr Zelensky responded sharply, calling Russia’s plans for Sumy and Kharkiv insane and vowing that Ukrainian forces will resist any attempt to seize those territories.

Behind the rhetoric lies a cold calculation. If Moscow cannot break through in the south and east, opening pressure in the north serves to stretch Ukraine’s defenses and to hand the domestic audience an image of initiative. For European capitals, which follow the war through the prism of their own security and the sanctions regime against Russia, this widening of the front means that any hope of a swift ceasefire is once again postponed.

What does Ukraine gain from striking deep in the rear?

Rather than wait for a Russian move, Kyiv has chosen to carry the war into Russia’s economic hinterland. Ukrainian drones struck a port and an aviation school in Taganrog, then set the Ilski refinery on fire, one of the plants that supplies the Russian domestic fuel market. The Institute for the Study of War notes that Ukraine is entering a new phase of isolating Crimea, with Yevpatoria left without power after drone attacks.

The logic is plain. Refineries and ports turn Russia’s depth into a vulnerable target and strike directly at the oil revenue that funds the war machine. Every plant hit means less fuel at Russian pumps, longer queues and pressure on prices, a message aimed as much at ordinary Russians as at the army. In the coming days Kyiv expects delivery of American Patriot systems, meant to strengthen the defense of the skies over cities that have been under attack for months.

For the region and for Serbia, this double move, Russia’s widening ground offensive and Ukraine’s strikes on energy infrastructure, means the war is not calming but changing shape. Instead of trench stalemate, we are increasingly watching a conflict in which victory is measured in kilometers as much as in barrels. Will the strikes on refineries and the buffer-zone announcement bring the negotiating table closer, or push it out of reach once more?