UK and Poland Sign Northolt Treaty to Counter Russian Threats

Keir Starmer and Polish Prime Minister Donald Tusk signed the Northolt Treaty at RAF Northolt in west London on May 27, 2026, establishing what Starmer called a generational uplift in defense and security cooperation between the two nations. The pact identifies Russia as the most significant long-term threat to Euro-Atlantic security and commits both countries to mutual assistance in the event of an armed attack.

The treaty's military provisions include the co-production of next-generation medium-range air defense missiles, increased joint procurement, and expanded use of uncrewed systems to reinforce NATO's Eastern Flank through joint exercises. Both leaders emphasized the need for increased European contributions to NATO and reiterated their support for Ukraine against Russian aggression.

Beyond defense, the agreement broadens cooperation to counter Russian hybrid threats, enhance energy and climate security, combat organized crime, and tackle migrant smuggling and human trafficking. The leaders also discussed the UK's ambition to establish closer ties with the European Union to enhance security and prosperity, and addressed the need for a lasting diplomatic resolution in the Strait of Hormuz.

Tusk stated the deal would help secure Poland and other nations against Russian threats. The visit concluded with a commemorative wreath-laying at the Battle of Britain Bunker museum to honor Polish pilots who served in the Second World War, underscoring the historical depth of the bilateral relationship.