Ukraine and Russia take the war underground as drones own the skies

The battlefield has moved below the grass. Ukrainian troops spent nearly two weeks crawling through a disused gas pipeline beneath the Oskil River and into Kupiansk, a frontline city Russia has been grinding to capture, according to the New York Times. Kyiv calls the mission Operation Veles. President Volodymyr Zelensky, who last week branded it a 'great success', said soldiers advanced 15 kilometres through a pipe just 1.2 metres wide, eliminated roughly a hundred Russian troops and pulled out more than 30 prisoners in fighting nobody could see.

This is a Russian trick that Ukraine has now made its own. Huseyn Aliyev, a Ukraine war specialist at the University of Glasgow, said Moscow pioneered the pipeline playbook and Kyiv is only now catching up, calling it the first time he knows of Ukrainians using the same methods. Zelensky's framing: Ukraine took the tactic, modernised it, and made it far more sophisticated and technologically advanced than the original.

There's a paper trail. Will Kingston-Cox of ITSS Verona pointed to Avdiivka in January 2024, where Russian troops surfaced behind Ukrainian fortifications through what looked like a drainage conduit. Moscow later used tunnels to claw back Kursk, then in Kupiansk, where the two sides fought for every foot of pipe. In September 2025, Russian independent outlet iStories reported that Moscow was stockpiling ammunition and supplies near the Kupiansk pipeline for a bigger offensive push.

The reason is overhead. Drones have saturated the sky, making open-ground assaults close to suicidal. Kingston-Cox said a group on open ground gets spotted long before it reaches anything, thanks to reconnaissance and attack drones. Ryhor Nizhnikau of the Finnish Institute of International Affairs put it bluntly: a tunnel is horrible, but a foot soldier at least knows his enemy is just ahead — and nothing is dropping from the sky when he least expects it.

The tunnels aren't invincible, and they're not everywhere. Gustav Gressel of Austria's National Defence Academy said radio-controlled drones lose signal at the entrance, and fibre-optic cables snag on corners, while nets and fishing lines can be strung up to detonate a drone early. But Aliyev noted large stretches of the front have no such infrastructure at all, and Nizhnikau stressed the underground fight is a support measure to the wider war, not a replacement for it.

Built in Soviet times to pump Russian gas into Europe, the pipeline network spans Kharkiv, Luhansk, Donetsk and parts of Zaporizhzhia — and both militaries have the maps, Nizhnikau said. Gressel added that city sewage and wastewater systems become battlefields too. Kingston-Cox reckons these high-risk runs can break local deadlocks, but warns a narrow pipe delivering soldiers a few at a time into a watched opening is extremely vulnerable. Until now Moscow owned this play. Veles shows Kyiv is ready to meet it underground.