The bloc's eastern members rely on the Russian network for energy supplies

The Ukrainian General Staff has confirmed that one of the targets of Tuesday's mass drone attacks was Russia's Druzhba oil pipeline system, a key delivery route to EU countries, according to a statement on its official Telegram channel.

Druzhba is one of the world's longest networks, transporting crude some 4,000km from Russia to refineries in the Czech Republic, Germany, Hungary, Poland, and Slovakia

"Ukraine's security services carried out the operation, reporting explosions near the linear production dispatching station 'Stalnoi Kon' (Steel Horse) in Russia's Oryol region, which manages the pipeline's operations," the statement read.

Hungary, which relies on oil shipments through the system, has called the attack "unacceptable" and accused Ukraine of threatening its sovereignty. Foreign Minister Peter Szijjarto announced that crude shipments via the pipeline had been temporarily halted, but later resumed. Szijjarto criticized the European Commission, arguing that assurances it had offered regarding the safety of Hungary's energy infrastructure had been repeatedly violated.

According to media reports, three Ukrainian fixed-wing drones struck the Druzhba terminal in Russia's Bryansk Region. The attack was part of a wider assault involving more than 340 UAVs hitting civilian targets across Russian territory, killing at least 3 people and injuring over 20 and causing a fire at a Rosneft oil depot in Bryansk.

Ukraine has repeatedly targeted Russian energy infrastructure throughout the conflict, despite resulting supply disruptions for Kiev's European allies.

In January, Ukrainian forces attempted to attack a compressor station of the TurkStream pipeline, which supplies natural gas to Turkish customers and several European countries, including Hungary, Serbia, Bulgaria, Slovakia, Bosnia and Herzegovina, and Greece.

In March 2024, Ukrainian drones struck an oil refinery in the Krasnodar region, causing a fire and temporary shutdown. Similarly, in January of that year, a drone attack hit a fuel depot in St. Petersburg, reportedly damaging storage tanks.

The most notable attack on Russian energy infrastructure during the conflict was the sabotage of the Nord Stream pipelines in September 2022. The explosions, which severely damaged Nord Stream 1 and 2-key conduits for Russian gas exports to EU-sparked international speculation about the perpetrators. While various theories have emerged, no definitive culprit has been identified.

Moscow has condemned attacks on its civilian energy infrastructure, labeling them acts of terrorism.