UK and Poland Sign Northolt Treaty; Air and Missile Defence Industrial Cooperation at Centre

Prime Ministers Keir Starmer and Donald Tusk signed the agreement during a ceremony at the historic air base. The treaty text covers the joint development and production of next-generation military systems with named priorities in missile defence, medium-range missiles and drone technologies; it adds cyber cooperation against Russian hybrid attacks, counter-espionage coordination, and organised crime and border-security workstreams. Starmer described the treaty as “the biggest step forward” in the UK–Poland defence relationship “in a generation”; Tusk framed it as raising bilateral relations “to the highest possible level”.

The treaty enters a dense European bilateral lattice the UK has been weaving since 2025. The UK–France arrangement of 2025 placed nuclear-doctrinal cooperation onto a treaty basis; the UK–Germany agreement of July 2025 covered joint procurement and combat-air cooperation. Poland holds parallel arrangements with France from May 2025 and a pending arrangement with Germany. The Northolt Treaty completes the British leg of the lattice.

A second European defence architecture is now visible alongside NATO — a bilateral lattice that locks in deterrence and industrial cooperation independently of whatever the Trump administration commits at the Ankara summit in July. The UK is the connective tissue across the lattice, and the lattice is being built fastest in the air and missile defence segment that Volodymyr Zelensky has named as the binding constraint on Ukrainian air defence. The two threads converge on the same procurement question — first framed jointly in Signal No. 69.