Europe Fails to Seize the Moment on Ukraine

European leaders still appear to be scrambling to create a consensus on both their priorities and support for Ukraine after a week of blunt US statements and jumbled diplomacy. Going in to a meeting of European leaders in Paris on 17 February, called by French President Emmanuel Macron during an uncomfortable Munich Security Conference, UK Prime Minister Keir Starmer appeared to break with caution by stating his readiness to deploy UK ground forces to Ukraine as part of providing security guarantees. There is already a small UK military presence in Ukraine in the form of a defence section in the embassy and a medical training team, but this proposal appeared to suggest a more substantial force of some description. It has been nearly a year since Macron first used a classic ‘refusal to rule out’ approach on sending French troops, but Starmer’s suggestion was the firmest sign yet of any other major European military appearing to be ready to follow suit.

The problems are multiple: there is no agreement on the purpose or size of any such force; some countries appear reluctant to even discuss the issue; and without US support, there is serious doubt as to the credibility of any such force acting as a deterrent to future Russian aggression. The proposal rests upon the significant assumption that any ceasefire agreement will include the deployment of Western forces; initial indications suggest that the Russians will strenuously resist such a provision. While repeated statements about European willingness to step up are welcome, and European defence spending overall has been on an upward trend since the NATO Wales Summit in 2014, only a serious, coordinated European effort can make a substantial contribution to Ukrainian security if we assume that the US will be significantly reducing its involvement. It might not be a good sign that countries like the Baltic states, which have a clear interest in how Russia is tackled, were not involved in the Paris discussions.

Peacekeeping is Not an Option

The function of any future deployment is key to determining size, capabilities, duration and prospects for success. Starmer has been ambiguous about this, only linking it to security guarantees for Ukraine. The first thing to do is to largely rule out ‘peacekeeping’ as it is classically understood, as both a function and a euphemism for a deployment. Peacekeepers are normally impartial, operate with the consent of all parties and are intended to separate combatants. Not only is there little prospect of European militaries being seen as ‘impartial’ after providing significant levels of military support to Ukraine, but adopting such a stance of is also largely undesirable: countries like the UK that have signed agreements with Ukraine want to be seen to deliver on those agreements.

Credibility is the Key

A more combat-orientated force intended to deter Russia – either through its own capabilities, or because an attack on it would bring further intervention – might be under discussion, but here Europe’s military limitations come to the fore. Some analysis suggests that small, so-called ‘tripwire’ forces have a mixed record in terms of creating a deterrent effect, and that a larger deployment is necessary for credibility. For a ground-heavy force, European countries will have a limited ability to deploy something that can be sustained for multiple rotations, potentially over several years. To begin with, the current Russian force attacking Ukraine is nearly 600,000-strong. Just looking at Donetsk and Luhansk alone there are around 230,000 troops arrayed against the Ukrainians, and this doesn’t take into account the ability of the Russian air force to strike the front lines with glide bombs almost at will, because of the commitment of most Ukrainian air defences to defending cities and infrastructure. Any European deployment intended to deter Russia would need to take these threats into account. 

For example, a serious UK deployment would represent a hefty portion of the deployable Army, from a total force of around 73,000. It might need to be an augmented brigade, with air defences and possibly an air-policing option from the RAF, or an air component able to attack Russian ground forces. Any combat jets, surveillance aircraft or tankers would face long-range Russian surface-to-air missile threats, or Russian jets. The ground force would have to draw on the handful of armoured and mechanised brigades available to the UK, and heavily commit the capabilities of the UK’s combat force, 3rd (UK) Division. The Army only has three or four such brigades: 12th and 20th Armoured Brigades and 7th Light Mechanised Brigade, perhaps with 16th Air Assault Brigade also involved. Assuming six-month deployments, this would essentially commit the deployable Army, if the current UK presence in Estonia (under 4th Light Brigade) remained in place. At best, it might represent a force of around 4,000–5,000 and involve the UK sending the bulk of its support and engineering capabilities, and would mean not being able to meet NATO commitments on reaction forces or the ‘strategic reserve’ the UK intends to provide. Additionally, 3rd Division is in transition and probably under-powered compared to a traditional UK division. This is before considering the command-and-control arrangements with other European militaries (and in-country with the Ukrainians), provision of additional defensive capabilities, intelligence-sharing, and rules of engagement to ensure it can operate effectively and if necessary fight. 

The scale of disagreement over any such deployment is an obstacle to putting a large force in the field. Poland – which has one of the largest European militaries – has already ruled it out, as has Germany, with Chancellor Olaf Scholz ‘irritated' at the fact such a deployment is even being discussed (admittedly, he faces imminent German elections). There is no suggestion that Turkey, the other sizable NATO military force, will be involved. Only France, of the major European spenders, appears positive. Here, the US reluctance to be involved is a major impediment to success. Not only does it remove US mass from the equation, but it also reduces the options for ground-based air defences (where the US is the major NATO provider), as well as leaving Europe to provide aircraft which could deal with Russian air defences, a task for which it is currently under-resourced. US military power, either directly involved or as the follow-up consequence of Russian transgression, would make a huge difference to the credibility of any force deployed into Ukraine, and the fact that US Secretary of Defense Pete Hegseth ruled out both US deployment and any option for use of NATO Article V dramatically reduces the deterrent effect of a Europe-only presence. Starmer, who has said that a US ‘backstop’ is essential, appears to be banking on his forthcoming visit to the US to influence President Donald Trump; the latter may have suggested he is still open to a role, but it will take a major breakthrough to change what has been a clear trend towards scepticism in Trump’s thinking. 

This leaves open the possibility of a much smaller force, possibly for training and support, aimed at helping the Ukrainians rebuild as part of any ceasefire – especially with the threat of another Russian attack in mind. The Ukrainian military would benefit from increased international support on its well-known personnel issues, which would also be consistent with the theme of the longer-term agreements some countries have in place, such as the UK’s ‘100 Year Partnership’. Yet it would also probably be disappointing to the Ukrainians that such a force would potentially contribute little in the way of serious deterrence, being well away from the (frozen) front lines, and probably unable to contribute major combat power. Meanwhile, it could still be a challenging commitment for armies like the UK, as it would disproportionately draw upon officers and non-commissioned officers, unless existing training efforts (like Operation INTERFLEX in the UK) were reduced in scale or ended. A training mission would still face the same credibility issues as a small tripwire force and the same lack of linkage to any large-scale US response. It might very well help make Ukraine’s own armed forces more capable and therefore resist a future renewal of the Russian invasion, but in the meantime it would not represent the sort of expanded commitment on meaningful security guarantees that Ukrainian President Volodymyr Zelenskyy appears to be seeking. 

European Rhetoric Meets Reality: Plus ça Change

With Europe excluded along with Ukraine from the opening phase of talks between the US and Russia taking place in Saudi Arabia, a major security offer to Ukraine represents one way of enhancing its military credibility and improving Ukrainian prospects in 2025. It might even strengthen Europeans in their dealings with the US. The scramble to Paris, followed by the lack of a definitive outcome, suggests that in spite of increased resourcing, European countries still lack a coherent plan for using funding or dealing with the Ukraine issue. And yet the outlines of Trump’s current approach became clear during the presidential campaign. Once his election was confirmed, Europe could have begun contingency planning for a coherent offer on both European security and Ukraine, or at least agreed their own position given the likelihood of US attention being drawn elsewhere. Instead, the Europeans are reacting to events and the outcome of initial talks, rather than playing any role in shaping them. There is still scope for European defence investment and coordination to play a significant role in support to Ukraine with increased production, and the German position may change after February’s elections, but this first test has instead highlighted continued division and a reliance on US military power that exposes grand European rhetoric.

© RUSI, 2025

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