During the NATO REPMUS/Dynamic Messenger 2025 exercises held in Portugal, Ukraine led a multinational naval team in a simulation where they took on the role of the 'enemy'. This team included military units from the US, UK, Spain, and other nations. The exercises were designed to test naval strategies and capabilities, revealing significant weaknesses within NATO's operational framework. In a striking development, the Ukrainian-led team reportedly 'sank' at least one NATO frigate during these training scenarios, showcasing the effectiveness of modern drone warfare.

The REPMUS/Dynamic Messenger exercises involved various training scenarios aimed at testing defensive and offensive strategies. According to a Ukrainian source involved in the exercise, the red team, which represented Ukraine and its allies, successfully defeated NATO's blue team in all five scenarios. These included critical simulations such as the defense of ports and the protection of naval convoys, illustrating effective tactical planning and execution by the Ukrainian-led coalition. The involvement of advanced naval drone technologies played a pivotal role in these outcomes.

The implications of these exercises are significant for NATO's future operations and its strategic assessments moving forward. The success of Ukraine's coalition highlights potential vulnerabilities that NATO may need to address, as well as the evolving nature of maritime warfare in the modern era. As tensions continue in the region, these exercises serve as a critical reminder of the need for adaptability and innovation within military strategies to counter emerging threats, particularly from unmanned technologies.