Ukraine widened its long-range campaign against Russian energy infrastructure on Sunday, with reported strikes on the Baltic oil hub of Primorsk and the NORSI refinery at Kstovo in Russia’s Nizhny Novgorod region, according to Russian regional authorities and Reuters reporting.

The attacks appear to form part of an intensifying Ukrainian effort to disrupt oil export routes, refining capacity and associated energy facilities deep inside Russian territory. Moscow said air defences had repelled the raids, but acknowledged damage at both locations.

In the Leningrad region, Governor Alexander Drozdenko first said a pipeline had been damaged near the port of Primorsk, one of Russia’s principal oil export outlets on the Baltic Sea. He later said the pipeline itself had not been damaged, but that shrapnel had struck a fuel reservoir in the port area, causing a leak. Russian authorities said there were no casualties and described the resulting fire as a controlled burn-off.

Primorsk is not a marginal target. Reuters reported earlier this week that satellite images showed the terminal had already lost at least 40 per cent of its storage capacity in Ukrainian drone attacks during late March. At least eight storage reservoirs, each with a capacity of 50,000 cubic metres, were reported damaged. The port can handle around one million barrels of oil a day, making it one of Russia’s most important export gateways.

Those earlier strikes had already disrupted operations. Reuters reported on 3 April that both Primorsk and Ust-Luga, Russia’s two key Baltic export hubs, were still unable to handle shipments after repeated attacks, forcing Russian refiners to look for more expensive alternative routes. Industry sources told Reuters that Primorsk had not been accepting diesel deliveries since 22 March.

The latest incident therefore suggests not simply a one-off strike, but continued pressure on infrastructure that was already degraded. Even limited additional damage at Primorsk could prolong export disruption and complicate storage and loading operations further, particularly if Moscow is forced to divert flows to rail or to smaller terminals. That is an inference from the reported condition of the port rather than an official assessment.

Further east, in Kstovo, Governor Gleb Nikitin said fire had broken out at the NORSI refinery after a drone attack. He said two facilities at the plant were hit, while a power station and several houses were also damaged. Preliminary information indicated no injuries. Reuters described NORSI as Russia’s fourth-largest refinery and its second-largest producer of petrol, with annual processing capacity of about 16 million metric tonnes, or roughly 320,000 barrels per day.

The significance of the Kstovo strike lies not only in the refinery itself but in the broader pattern it reflects. Ukraine has repeatedly targeted oil depots, refineries, pumping systems and port infrastructure in an attempt to reduce Russian fuel revenues and create strains across the logistics chain that supports both the civilian economy and military operations. Ukraine has stepped up such attacks over the past month in an effort to damage one of Russia’s main revenue sources and weaken its war-making capacity.

What remains unclear is the precise operational effect of Sunday’s attacks. Russian officials acknowledged fires and damage, but the full extent of disruption at Primorsk and NORSI has not yet been independently quantified. In particular, there is no public confirmation so far of how long the refinery may be offline, whether the associated power damage will materially affect output, or how quickly Primorsk can resume normal handling operations.

Still, the strategic direction is becoming harder to miss. Ukrainian strikes are increasingly concentrated on the energy sector, especially the infrastructure that links production, storage, transport and export. Rather than focusing solely on symbolic targets, the campaign appears designed to erode Russia’s ability to refine crude, move petroleum products efficiently and load export cargoes from major terminals.

For Moscow, that presents a layered problem. Damage to a storage reservoir, a refinery unit or a local power facility may each be manageable in isolation. Repeated strikes across several nodes of the same system are more difficult to absorb. Russia can repair tanks, reroute cargoes and reinforce air defences, but those measures impose cost, delay and uncertainty.

Sunday’s strikes on Primorsk and Kstovo do not, by themselves, transform the balance of the war. But they underline a continuing trend: Ukraine is sustaining deep strikes against Russian energy assets, and Russia is still struggling to shield all of them.