On 23 October 2024, at Trinity House in London, John Healey, the British Secretary of State for Defence, and Boris Pistorius, the German Federal Minister of Defence, signed the Agreement on Defence Co-operation between the two ministries, in duplicate, in English only. It is not the Lancaster House treaty of 2010, with France. It is not the NATO Treaty. Section 10 is plain: it is not considered a treaty under international law and does not create any legally binding rights or obligations. It enters into effect on the day of signature; either participant may terminate it at any time, with ninety days’ prior written notice through diplomatic channels.

The participants place their defence policies on common interests, values and responsibilities. Greater bilateral defence co-operation, they write, strengthens NATO, the cornerstone of their collective defence. They seek interoperability, interchangeability and integration of their armed forces, and a robust, competitive technological and industrial defence base as a strategic and economic necessity for Europe. Section 1: a long-term partnership — Euro-Atlantic security; the two defence industries, research and technology, co-operative equipment programmes; interoperability across all domains and NATO standardisation; mutual support for defence action in the United Nations and NATO, and complementary NATO–EU co-operation; long-term military support for Allies and partners.

Section 2: a Defence Ministerial Council — the two ministers, with chiefs of defence as required — decides by consensus, sets the long-term aims, and settles disputes of implementation. It oversees three fora: the Military Steering Committee (armed forces, doctrine, interoperability); the Ministerial Group on Equipment and Capability Co-operation (MECC), industry and capability, minimising national constraints; and a Defence Policy Dialogue, including a dedicated sub-group on nuclear issues, in a shared format with the foreign ministries. Written agreements or arrangements may follow on specific points. Costs and benefits are to be shared equitably, unless otherwise provided. Classified information follows the security arrangements between them and applicable NATO instruments. Disputes of interpretation go to negotiation through diplomatic channels. Amendments, in writing, from the date of last signature. Section 11: the text does not affect each participant’s other defence and security agreements.

The British ministry’s announcement, with the signing, lists the “lighthouse” projects: long-range strike weapons farther and more precise than current systems, including Storm Shadow; a large-calibre gun-barrel plant in the United Kingdom, more than 400 jobs, steel from Sheffield Forgemasters, Rheinmetall; training on NATO’s eastern flank; Boxer vehicles and land drones; protection of North Sea cables; German P-8 aircraft, periodically, from RAF Lossiemouth; drones alongside fighter jets; German Sea King helicopters with modern missiles, for Ukraine; integrated air defence. Those points sit in the communiqué, not as articles in the five-page text. Healey said the agreement would be put on a legal footing in a wider UK–Germany treaty, pledged by Starmer and Scholz in August.

Trinity House is the home of England’s lighthouse authority, from Henry VIII on; hence the name. It is not the UK–Romania defence agreement of 13 November 2024.

Trinity House, Tower Hill, the place of signature. Façade, 2015, not the table. Wikimedia Commons, CC BY-SA 4.0.

For context: Trinity House Agreement. The text: UK-Germany Trinity House Agreement on Defence.