Prime Minister Keir Starmer and German Chancellor Friedrich Merz on July 17 signed the first comprehensive bilateral treaty between their countries since World War II. Dubbed the “Kensington Treaty,” the agreement, inked at London’s Victoria and Albert Museum, vows broad cooperation on defense, the economy and more, at a time of rising threats to Europe. Merz hailed the accord as “historic, the first major bilateral agreement” between Britain and Germany to deepen defense ties and boost growth. Starmer called it “an expression of our shared aims and values” and “a practical work plan setting out 17 major projects” to deliver tangible results. The treaty follows closely on a state visit by France’s Emmanuel Macron, underscoring a renewed E3 (France–Germany–UK) partnership in European security.
Main Provisions of the “Kensington Treaty”
The treaty lays out wide-ranging commitments across six pillars – diplomacy, defence, internal security, economy, people-to-people and climate/energy – echoing frameworks seen in recent UK–France and EU–UK agreements. Key elements include:
Defense and security cooperation: Britain and Germany pledge a mutual-assistance clause “in case of armed attack,” declaring they see “no strategic threat to one which would not simultaneously pose a threat to the other”. Although both are NATO members, the treaty formally reaffirms Article 5 commitments while adding new joint projects. These include work on long-range strike missiles (to counter Russia’s aggression) and expanded joint military exercises. The pact also commits the two governments to close dialogue on shared defense issues, including any nuclear-related matters. Defense industries will deepen collaboration through initiatives such as unified export campaigns for jointly-built arms like Typhoon fighters and Boxer vehicles, and further develop shared systems.
Migration and internal security: To tackle illegal immigration, the treaty enshrines “joint action” against migrant smugglers and tighter cooperation between law enforcement. Germany agreed to criminalize facilitation of irregular migration to the UK by year’s end. Both sides will share intelligence and coordinate operations (e.g. via the Calais Group and Berlin Process) to break smuggling networks. Starmer praised this as evidence that “we mean business” on securing borders, citing prior German commitments to toughen laws and close down smuggler warehouses.
Trade, energy, and transportation: The treaty aims to revive the post‑Brexit economic relationship. It calls for joint export campaigns and new industrial ties to boost trade. Both sides pledged to work on an ambitious London–Berlin direct rail link, and to develop new North Sea energy projects, including hydrogen pipelines. Other agreed projects include opening more German airport e-gates to UK passengers and harmonizing arms-export rules to third countries (the UK is joining a Franco-German export pact). These measures are meant to accelerate infrastructure links and trade flows, addressing the decades of declining UK–Germany commerce after Brexit.
Science, technology, and climate: A Strategic S&T Partnership is established, focusing on emerging fields. The treaty calls for joint research in quantum computing, AI, semiconductors, space and clean energy. For example, the two countries will develop collaboration on semiconductor manufacturing and coordinate on climate goals, reaffirming their shared commitment to limit warming to 1.5°C. Plans were also announced for a strategic partnership in satellite and aerospace projects, complementing the security aspects.
People-to-people links: The agreement includes new visa and education initiatives: UK pupils can travel visa-free for school exchanges, and a joint expert group will promote more cultural and business exchanges. It also sets up a bilateral summit schedule, with ministers meeting annually and leaders every two years, to ensure follow-up on these commitments. Observers noted these institutional links send “important signals” of shared intent, beyond the treaty’s specific clauses.
Taken together, the provisions cover some 17 pilot projects (spelled out in a government annex) ranging from Ukraine reconstruction aid to joint cyberdefense exercises. Notably, many announced measures (like migration policing and open e-gates) build on steps the countries were already taking, but the treaty packages them in a formal framework.
Reviving the E3 and European Security
Merz’s visit followed Macron’s London trip by one week, underlining a deliberate revival of the E3 format (UK–Germany–France) as a core of European defense diplomacy. Analysts say the Kensington Treaty, together with the France–UK deal, anchors the E3 “back at the heart of European security,” allowing the three powers to coordinate more nimbly on crises than the wider EU or NATO structures.
The pact comes as Europe faces multiple challenges: Russia’s war in Ukraine, worries over U.S. commitment under President Trump, and soaring U.S. trade tensions. A recent survey found British trust in the United States has fallen sharply (from 53% to 38%), with growing public support for closer ties with Europe. In this climate, British experts say Starmer is pivoting post-Brexit towards the continent. The treaty was negotiated by Labour and the SPD (Germany’s governing partner) and signals a “reset” of ties that had frayed since Brexit. As one commentator put it, London and Berlin view the agreement as “complementary to their enhanced cooperation with Paris,” rather than a rebuke to Brussels.
Within NATO, the UK and Germany emphasize that Article 5 remains their bedrock. The mutual-assistance clause is largely symbolic, a pledge to each other that “if one bleeds, the other bleeds,” but it sends a political message about standing together against shared threats. Both leaders stressed that Russia’s aggression is “the most direct threat” they face. France, which co-chairs a so‑called “coalition of the willing” with the UK for Ukraine support, has welcomed the deeper ties: the Chatham House institute noted this treaty helps unify the three biggest European armies amid uncertainty about Washington’s role.
Reactions and Road Ahead
British and German officials uniformly praised the treaty as visionary. Starmer said the Kensington Treaty “measures just how close our countries are” in a volatile world. Merz, while lamenting Brexit (“we deplore it deeply”), called the accord a new chapter in ties with the UK. Both leaders highlighted plans to send more military aid to Ukraine: Merz confirmed they are working on long-range strike systems for Kyiv and “Ukraine will soon receive substantial additional support.”
Critics note that some treaty elements merely formalize existing arrangements. For example, the mutual-defense pledge overlaps with NATO obligations, and e-gates for UK travelers were already negotiated in the EU context. In London, opponents of Starmer’s government questioned why certain promises (e.g. on migration) were already in motion. But most commentators agreed the treaty is a powerful political signal. The BBC said the 23-page agreement lives up to much of the “hyperbole” surrounding it, and crucially establishes a high-level forum for policy coordination.
In Germany, the deal reinforces Merz’s aim to show Germany as a committed security partner. Observers in Berlin note Germany’s trade with the UK fell from third-largest (2016) to ninth (2024) after Brexit, so the treaty is seen as boosting commerce and industry. One German official said the pact confirms “there is no strategic threat to one which would not be a strategic threat to the other,” and binds Berlin to support UK initiatives on everything from sanctions to climate.
Moving forward, both governments have set up regular review mechanisms. Ministers from foreign, defense and economic departments will meet annually to drive the 17 projects, and leaders will reconvene every two years. This creates a “dynamic” that could tighten UK–German ties regardless of any single political leader. However, analysts caution that such bilateral pacts cannot by themselves fill all post-Brexit gaps. As one expert remarked, the E3 is “flexible” but still limited to what London and Paris–Berlin can do outside the EU and NATO frameworks.
In sum, the Kensington Treaty represents a watershed for the UK’s foreign policy under Starmer. It showcases the UK forging new security and industrial partnerships in Europe, and Germany cementing ties with its key neighbor. The pact’s success will hinge on sustained political will: its 17 projects must survive future election cycles and global shocks. For now, it stands as a symbol of a closer post-Brexit alliance: one that aims to deter common threats and nurture shared prosperity on a continent facing turbulence.