Europe’s Minilateral Moment

Europe is experiencing a ‘minilateral’ revolution as its leaders huddle up with trusted neighbours and partners across the continent to build defence and security relationships. This political shift is driven by the twin challenges of growing threats, notably from Russia, and hostility from the Trump administration, which together have forced Europe’s leaders to look for new ways to assert leadership.

On a 18 November 2025, Prime Minister Starmer flew to Berlin for a dinner meeting with his German and French counterparts in the E3 format, a grouping originally established to represent Europe in nuclear negotiations with Iran. Ultimately, there was little media coverage of the meeting other than noting that the leaders discussed the situations in Ukraine, the Middle East and Iran, as well as economic issues. Leaders expressed support for working together on foreign and security policy, and highlighted cooperation with Poland and Italy. The E5 – a group having been set up earlier in 2025 to bring together the continent’s largest defence actors – had met days earlier at the defence minister’s level (plus EU High Representative) to coordinate support for Ukraine.

The E3 Berlin discussions were soon overtaken by the emergence of a US-Russia peace proposal to end Russia’s war against Ukraine. Yet the E3 mechanism has been at the core of the various European political consultations to cobble together a response, with the national security advisers of France, Germany and the UK (plus Italy) attending the Geneva discussions on the peace proposal and the three leaders coordinating (with Ukraine) the drafting of an alternative (European) peace plan. Alongside the E3, the Coalition of the Willing, a group convened by the UK and France, involving 31 – primarily European – countries provided key support. At the same time, the Nordic Baltic Eight issued their own separate statement on the peace proposal.

This emergence of sub-groupings of European leaders on foreign and security policy is not a new development. The frequency of such meetings has, though, become supercharged recently and there has been a proliferation of ad hoc formats as Europe’s security crisis has escalated. Fundamentally, the new turn to minilateralism is a response to the difficulties that Europe is experiencing in asserting political leadership on foreign and defence issues through existing multilateral formats faced with a more hostile international environment and growing uncertainty of the US commitment.

Europe’s Established Security Architecture is Faltering

Russia’s war against Ukraine has seen a new commitment by European countries to the continent’s established multilateral security arrangements. Finland and Sweden have become NATO members and at the Hague Summit in the summer of 2025, European members of the alliance committed to spending 5% of GDP on defence by 2035. Equally, the EU has made important steps to become involved in defence, notably in advancing its role in the European defence industry. Moscow’s actions have even seen significant strides in NATO-EU cooperation after decades of mutual suspicions.

Yet the measures taken to enhance Europe’s principal security organisations have done little to counter the sense that Europe has become ever weaker in ensuring its own security. Nowhere has this been clearer than over the Ukraine war, with the Trump administration’s preference to negotiate the end of the war without European involvement. Indeed, the US administration has even been ready to make commitments on behalf of NATO and the EU without seeking their agreement.

In explaining Europe’s marginalisation, some have suggested that the problem lies in a European psychology of weakness. This is not the key issue. The challenge of responding to the new international security environment has highlighted the structural weakness in the set-up of Europe’s security architecture – crucially the reliance on the United States. As uncertainty about the US commitment to Europe grows, the underpinning of Europe’s multilateral order is fracturing and the consensus-based and process driven multilateral formats are struggling to respond.

The initial reaction by Europe to the growing uncertainty has been to double down on NATO – to create a European pillar based on producing the defence capabilities needed if the US pulls back its forces from the continent. Yet, Trump’s actions have made it is increasingly clear that the US provides something more important than capabilities to NATO – its leadership and strategic vision. Former NATO Secretary General Jens Stoltenberg’s recent autobiography sets out starkly the irreplaceable political role that the US under President Biden played through NATO in shaping Europe’s response to Russia’s invasion of Ukraine.

Under President Trump, the US has lost interest in leading the alliance. The brevity of the NATO Hague Summit Declaration reflected the lack of US engagement in a future strategic orientation for the alliance. The decision of US Secretary of State Rubio to skip the NATO minister’s meeting to discuss the Ukraine war peace plan has further underlined that NATO’s role as a forum for political-military issues is being weakened. Some reports indicate that Washington is ready to handover its crucial leadership role to Europe by 2027.

Yet, with doubts emerging about NATO’s ability to provide leadership on European security, the situation for the Europe Union is no better. The EU has struggled to adapt to the new geopolitical and geoeconomic realities. Hamstrung by the inability to respond effectively to key challenges, inter alia Russia and the Middle East, because of requirements for consensus, slow and cumbersome decision making, and the diverse member state threat perceptions and security interests, the EU is marginalised from the key decisions affecting international security.

The Minilateral Response to Assert European Leadership

Faced with the difficulties of crafting effective responses through Europe’s multilateral organisations, leaders are looking to meet in a plethora of minilateral and sub-regional groups. While formats like the Coalition of the Willing or the E3 attract the greatest attention, there are a host of other arrangements including the E4, E5, Nordic-Baltic 8, the Weimar Triangle and Weimar Plus, the Joint Expeditionary Force, as well as numerous bi- and trilateral groupings. In the summer of 2025, the UK, Germany and France triangulated their relations through a series of summits, with new (UK-Germany) and upgraded (UK-France) security treaties.

Governments are turning to those they trust most to form coalitions. Minilateralism involves small groups of countries working together, often neighbours, who share common threat perceptions and values, and are strategically aligned. It also reflects risk spreading at a moment of uncertainty in Europe by investing in key relationships and diversifying partnerships. But above all, minilateralism is driven by a search for opportunities to build leadership and set agendas at a moment when Washington appears ready to abdicate its leadership role.

Structuring Europe’s Security Architecture Spaghetti

European security now stands at a crossroads in its post-World War two history. For the first time, not only are there doubts about the commitment of the United States but Washington appears actively hostile to European interests, even aligned with Russia, and potentially ready to forge new international mechanisms, such as the C5 (US, Russia, China, Japan and India) without Europe. As President Trump has observed, European leaders talk but they don’t produce and ‘Europe doesn’t know what to do’.

Against this backdrop, European countries urgently need to find new ways to assert their security interests, advance political agendas, and to build international leverage. Minilateralism, with its flexibility and ability to operate quickly, has emerged as the most viable way for European countries to assert their leadership and to build effective networks of cooperation. But there are risks in the emergence of multiple disconnected coalitions of the willing, and concerns amongst smaller states that they are vulnerable to a return to big-power politics. This is the moment for European countries to think carefully how to shape current developments to ensure the long-term strategic coherence of European countries as security actors.

European security is likely to continue to evolve as a tangle of national, minilateral and multilateral formats. There is, thus, an urgent need to establish a key political centre that can coordinate across these various formats and leverage collective European responses. The E3 is fast evolving as a mechanism bringing together the largest European states while offering the flexibility to connect to other actors (Ukraine) and other minilateral formats, as well as coordinating positions and creating political leadership across and within NATO and the EU.

Now is the moment to advance ways to give this grouping broader political and strategic weight and to move it beyond the focus on crisis response – a mandate to address the full range of European security challenges, a meeting calendar, the creation of working groups on key issues with necessary staffing support, the appointment of envoys to drive diplomatic processes (Ukraine-Russia war) and regular meetings with other key minilateral formats. Such a shift would not be designed to replace existing European security arrangements. Instead, it would provide a European political mechanism better able to quickly catalyse shared interests, build common positions amongst various groupings, and assert these in a strategic way at the regional and international level. Europe can then begin to reverse its marginalisation, at this critical moment.

© RUSI, 2025.

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