A military exercise off the coast of Portugal has revealed a major vulnerability in NATO's naval forces, the German newspaper Frankfurter Allgemeine Zeitung reported, citing its sources.
A multinational naval team under Ukrainian leadership, playing the role of the “adversary“, exposed the vulnerabilities of NATO's naval forces during the REPMUS/Dynamic Messenger 2025 exercise and “sink“ at least one allied frigate.
Five training scenarios off the coast of Portugal practiced defense of ports and convoys, as well as attacks on naval targets. In all five cases, the “red” (the Ukrainian team) defeated the “blue” NATO forces. They also used Ukrainian Magura V7 naval drones - small unmanned high-speed boats that can attack enemy ships.
The Ukrainian Navy has been using similar naval drones, as well as missiles and other weapons, to push Russian forces out of the western Black Sea since the invasion began, even though Kiev does not have large warships.
In April 2022, the missile cruiser “Moskva” - the flagship of the Russian Black Sea Fleet - was sunk. The fleet was then forced to move its main base from Sevastopol in occupied Crimea to Novorossiysk, further east. But even in this port last December, a Ukrainian underwater drone managed to attack a Russian submarine.
A NATO spokesman described the exercise as an “important milestone”. Dozens of units – sea drones, aircraft, and larger warships participated in the five scenarios. At the end of the fourth week, according to information from Kiev, the “red” team emerged victorious.
The exercise clearly showed that unmanned systems, combined with real combat experience and well-tested planning, pose a “real threat” to NATO naval forces – especially since the alliance is still not sufficiently prepared for such attacks.
For example, in a simulated attack on a convoy, the “red” achieved so many “hits” against a frigate that in a real situation it would have sunk.
A NATO spokesman confirmed to FAZ that in this exercise, for the first time in the history of the alliance, the Ukrainian naval forces led and coordinated the “adversary“ forces – “a historic milestone that confirms the growing role of Ukraine in NATO exercises“.
The exercise demonstrated the latest trends in naval warfare. According to NATO, “the Ukrainian leadership brought realism to the exercise and stimulated innovation, as well as the development of new tactics within the alliance“. From Ukraine's front-line experience, NATO has drawn “valuable lessons“ that support the development of new capabilities “to deal with real threats“.
Last fall, NATO had the opportunity to learn a similar lesson, but on land. During an exercise in Estonia, about ten Ukrainian drone specialists managed to disable two NATO battalions. Brussels admitted at the time that they were "shocked" by how poorly prepared the allied forces were for drone warfare of the type being waged in Ukraine today.