How to unleash the potential of the UK-German relationship

Carolyn Rowe, Ed Turner, Tobias Hofelich and Jannike Wachowiak look at the UK-German relationship since Brexit and consider how the two sides could work more closely together. 

The UK’s relationship with Germany is multifaceted, complex and deep. The UK was one of the ‘occupying powers’ after the Second World War. The stationing of British troops in Germany until 2020 created lifelong bonds between people, contributed to cultural exchange, and shaped German institutions. Footballing rivalries are epic, with the hugely successful 2006 World Cup a game-changer in many Brits’ perception of Germany. Yet Britain and Germany did not always see eye-to-eye on matters such as European integration and Prime Minister Margaret Thatcher, fearful of the potential power of a united Germany, was initially sceptical about German reunification. Despite their differences, the two countries were often allies in the European Union, frequently in agreement on questions about trade openness and competitiveness, thus functioning as a counterweight to French and southern European interests.

This changed – dramatically – with Brexit. There was some acrimony towards Germany in the run-up, with British politicians naively expecting then Chancellor Angela Merkel to intervene to give them a better deal in the pre-referendum renegotiation of the terms of membership. But far more profound was German consternation at the UK’s decision, being compared variously (in the many interviews we have conducted for a research project on the UK-German relationship) to a messy relationship break-up, and an act of self-harm. Precisely because of strong German ties to and affinity with the UK, the distress at Brexit was felt by German decision-makers, many of whom had lived and, importantly, studied in Britain, all the more acutely. Throughout the ‘Brexit period’ (from the referendum in 2016 through, at least, to the signing of the Windsor Framework in 2023), the UK’s difficult relationship with the EU had a profoundly negative impact upon bilateral relations with Germany. There was a sense that ‘perfidious Albion’ was seeking to divide and conquer EU member states by looking for bilateral dialogue with them rather than working through the European Commission; there were worries that if the UK got ‘too good’ a Brexit deal, other countries might follow it out of the EU, and European integration, a cornerstone of post-war (West) Germany’s DNA, would be fatally undermined. There was also a strong sense that the UK’s proposed terms of its future relationship were unreasonable, often decried as Rosinenpicken, or ‘cherry picking’. There was fury when the UK failed to honour its commitments in the Withdrawal Agreement and even owned up to a ‘specific and limited’ breach of international law, while Boris Johnson – about as different a politician to Angela Merkel as it was possible to be – was hugely disliked and mistrusted.

Things started to improve with the election Rishi Sunak as Prime Minister, and the signing of the Windsor Framework. The German government, led by the social democratic SPD, welcomed the election of a new Labour government under Sir Keir Starmer in 2024. Labour and SPD politicians had quietly got to know each other in the years before the general election, laying the groundwork for closer bilateral cooperation with security and defence being a point of focus. Starmer’s visit to Berlin, just weeks after his election, in August 2024, kicked off work on a new bilateral treaty. There was a hiatus after the German government collapsed later that year, but the Kensington Treaty was finally agreed in July 2025, promising many new forms of intergovernmental co-operation as well as concrete ‘lighthouse projects’ such as co-operation on defence industrial co-operation, North Sea energy, and irregular migration, and enshrining deeper commitments on defence which had been set out in the Trinity House UK-Germany defence agreement of October 2024.

On its own, though, the Kensington Treaty will achieve little, without ongoing commitment, especially political commitment, in the two countries. It will not be sufficient just to talk at moments of pressing crisis, and consistent investment of time is needed. The various ministerial dialogues set up under the Kensington and Trinity House Treaties will help, however, ministers and officials will have to prioritise areas of engagement, and the ghost of Brexit will continue to lurk in the shadows. For instance, Germany rapidly backed off a bilateral agreement on youth mobility when the EU decided to get involved.

The UK has to tread a careful line, never asking Germany to ‘choose’ between the UK and the EU, but still using bilateral channels to influence the EU, such as securing a more accommodating stance on potential UK membership of the SAFE programme. Narrowly transactional behaviour by the UK in the sense of ‘we give you security, you help us on trade’ will fail. But there are links between different strands of the relationship, with fluid boundaries between different aspects of security such as questions of defence procurement and deployment, shared economic projects and labour mobility. The UK should use these links to create a narrative of mutually beneficial relations and real partnership.

The importance of bilateral trade diplomacy should also not be underestimated: precisely because of the greater complexity in trading relationships in the post-Brexit world, active trade diplomacy is more important than ever, and the Department for Business and Trade needs sufficient capacity to deliver it.

So, what is needed to unleash the potential of the UK-German relationship?  Four things stand out. First, it must be understood in Britain that sound relations with the EU form the baseline for bilateral cooperation with Germany. Secondly, there needs to be consistency in political commitment, with full delivery on the Kensington Treaty. Thirdly, dialogue should not just be for ministers and senior officials, but also a wider cast of parliamentarians (recent visits to Berlin by select committees are an excellent start), and other public servants, for instance through secondments. And finally, civil society links are crucial: even though fewer UK schoolchildren are learning German, school and youth trips are more important than they were before Brexit, while sporting and cultural exchange is essential, especially where it reaches parts of society that would not normally be taking city breaks to Berlin or cruising down the Rhine. The commitments made in the Kensington Treaty are welcome. Now, these must be delivered on. In the post-Brexit world with a destabilised transatlantic relationship and war in Europe, strong UK-German relations are more important than ever before.

By Carolyn Rowe, Head of Department, Society & Politics at Aston University and Co-Director of the Aston Centre for Europe; Ed Turner, Reader in Politics at Aston University and Co-Director of the Aston Centre for Europe and acting chair of the International Association for the Study of German Politics; Tobias Hofelich, Research Associate, Aston University; and Jannike Wachowiak, Research Associate, UK in a Changing Europe.

This blog draws on a series of roundtables organised by the Aston Centre for Europe and UK in a Changing Europe in March 2026. The discussions were supported by funding from the German Academic Exchange Service (DAAD).