NATO has used Ukrainian forces and Ukrainian-made uncrewed surface vessels as an opposing “red team” in exercises, Adm. Pierre Vandier, the alliance’s Supreme Allied Commander Transformation, told Breaking Defense in an article published November 11, 2026. The report quotes a senior official saying the aim is to “trigger an adaptation cycle” within the alliance.

What Vandier said

  • “What we’ve done so far, we took some experience from Ukraine,” Vandier said, describing Ukrainian forces and sea drones being given the opposing role, “the red team against the blue force of NATO.”
  • He did not name a specific exercise, according to Breaking Defense.
  • On drone swarms he said the question is “how many drones as part of a swarm will submerge a navy, where is the known limit to trigger adaptation.”
  • “So you cannot envisage any kind of operations without counter-drone [defenses],” he said, adding that forces conducting amphibious operations face both naval and aerial drones.
  • On anti-submarine warfare, which Breaking Defense says he described as one of the alliance’s main domains of concern: “I think the Russians have kept pace in building some good capabilities.”

Ukraine’s claim about REPMUS 2025

The only exercise named in the article is REPMUS 2025 off Portugal, and the reference comes from Ukraine’s Ministry of Defense, not NATO. Breaking Defense reports that the ministry says its red-team forces beat NATO members in “five out of five combat scenarios,” reportedly in part using uncrewed surface vessels. The article does not report a NATO response to that claim.

Other details

Breaking Defense also describes “Fight Club,” a NATO initiative within the Joint Warfare Centre that is part of a five-year campaign and produces hypothetical scenarios to test operational concepts and doctrine.

What the article does not say

The article does not say which NATO exercises used Ukrainian red-team forces apart from the REPMUS reference, how many Ukrainian personnel or vessels took part, which drone models were used, which allies participated or what the drills changed in NATO tactics.

Sources and notes

This post is based on Breaking Defense’s article by Elisabeth Gosselin-Malo, published November 11, 2026. Lens read it as extracted text. Lens did not read the Ukrainian Ministry of Defense statement on REPMUS 2025 or any NATO release, and did not contact NATO or the ministry.

Image: support boats off Setúbal, Portugal, during NATO’s REPMUS 2025 exercise on September 23, 2025, U.S. Navy photo by Jhon Parsons, public domain, via Wikimedia Commons.