The United Kingdom and Germany have signed a landmark treaty pledging mutual defence support in the event of an armed attack, marking a significant reset in relations between the two countries. The pact also includes cooperation on trade, migration, and advanced weapons development, as both sides seek to reinforce European security amid growing global threats.

British Prime Minister Keir Starmer and German Chancellor Friedrich Merz formalised the agreement during a ceremony in London, with the leaders presenting it as a key step toward restoring deeper Anglo-European cooperation after years of Brexit-related tensions. The treaty commits both nations to assist one another in case of an armed attack, underscoring mutual concerns over an increasingly aggressive Russia and doubts about US commitment to NATO under President Donald Trump.

Officials from both sides stressed that this agreement does not replace NATO’s collective defence guarantee but serves to reinforce European security at a time of uncertainty in transatlantic relations. Germany, lacking nuclear weapons of its own, continues to rely on the UK and France for deterrence while enhancing bilateral security frameworks.

New Missile Project and Industrial Cooperation

Alongside the mutual defence clause, the agreement outlines plans to jointly develop a long-range missile system known as the Deep Precision Strike capability, expected within the next decade. With a range exceeding 2,000 kilometres, the project aims to boost both nations’ defence industries through significant investments and to ensure Europe’s ability to deter future threats independently.

The treaty follows groundwork laid last year between Starmer and Merz’s predecessor, Olaf Scholz, and reflects growing European cooperation on security in response to geopolitical shifts.

Addressing Brexit Fallout and Migration

The pact also tackles lingering Brexit-related challenges, with commitments to improve coordination on trade, transport, and irregular migration. Germany has agreed to enact new laws by year’s end to criminalise facilitating irregular migration to the UK, addressing British concerns about cross-border security.

Both leaders view the agreement as a model for future cooperation between Europe and the UK, with Merz citing it as part of efforts to confront issues like Trump’s trade policies and the war in Ukraine.

Economic Cooperation and Investments

Beyond defence, the agreement includes over £200 million in commercial investments aimed at creating 600 jobs in the UK. German companies like Siemens Energy and AI firm Cognigy GmbH are expanding operations in Britain, reflecting broader ambitions to rebuild post-Brexit economic ties.

Political analysts suggest the treaty offers a strategic distraction for both leaders amid domestic challenges—Starmer grappling with policy U-turns at home and Merz facing coalition tensions in Berlin.