Russian ships stopped moving through the Sea of Azov entirely for nearly a week in July after Ukrainian drones struck vessels carrying fuel and supplies to the Russian military, according to Ars Technica. This represents the latest blow in a year-long campaign in which Ukraine has attacked Russian supply lines by sea—a critical way Russia moves troops, weapons, and fuel to occupied Crimea and forces fighting along the southern coast.

On the night of July 12, Ukrainian drones hit 14 ships in the Azov—ten oil tankers and four ferries—bringing the total number of Russian vessels struck by drones to 91 since the campaign began, according to Euromaidan Press. Video released July 9 showed a Russian oil tanker under drone attack in the same waters, per Le Monde. The Sea of Azov is one of Russia's last reliable shipping routes—other paths across the Black Sea and through the Kerch Strait have already faced repeated Ukrainian strikes.

Ukraine's assault on Russian sea supply lines started in mid-2025, according to the Institute for the Study of War, beginning with attacks on ferry services to occupied Crimea. By late June, Ukrainian strikes were reaching oil supplies, power plants, weapons convoys, and bridges in Crimea, getting past Russian air defenses, Al Jazeera reported. A New York Times investigation published July 4 documented repeated strikes on Russian ships in Crimean waters that forced Russia to stop ferry service and rely instead on narrow land routes and the Kerch Strait Bridge—a single bridge that connects Russia to the peninsula.

By early July, the BBC reported that Russia faced a squeeze: land routes to Crimea were already at risk, and sea routes were now under fire, per BBC reporting from July 9. The Azov shutdown pushed this problem further east, into a waterway Russia had believed was safe from Ukrainian attack.

What makes these drone strikes different from earlier attacks is the weapon itself. Ukraine is using one-way attack drones—cheap, disposable aircraft that fly straight into their targets rather than return home—to hit ships far from shore, according to Ars Technica. This approach lets Ukraine strike ships repeatedly without using up expensive cruise missiles or naval ships it doesn't have in large numbers. The Sea of Azov is shallow and mostly surrounded by Russian-controlled land, which makes ships there easier targets for drones launched from nearby Ukrainian positions.

Russia's shipping options have shrunk considerably. Ferry service to Crimea has stopped. Shipping in the Azov shut down for a week. Russia now relies mainly on land routes—roads through Krasnodar Krai and the single Kerch Strait Bridge—to move supplies, the BBC reported. But these land routes have already been targeted by Ukraine in the past.

Current reporting does not confirm whether Russia has restarted shipping in the Azov since the shutdown, or if ships have returned at lower numbers. The most recent reports from late July describe a corridor that remains under threat, not one that has been permanently closed or fully restored.

The real takeaway is the pattern over the past year. Ukraine's maritime campaign has grown from hitting scattered ships to systematically attacking Russian supply lines across the Black Sea, around Crimea, through the Kerch Strait, and now in the Azov. Since Russia built its military operations around Crimea as a supply hub and staging ground, losing sea routes—even temporarily—puts stress on an already stretched supply system. Whether this logistical pressure eventually hurts Russia's ability to fight on the battlefield, or simply causes inconvenience to supply operations, is not yet clear from available reporting. That is the key question to watch as Ukraine continues this campaign.