After almost four years of brutal fighting, Russia and Ukraine may finally be on the cusp of a comprehensive ceasefire. Yet, the only security guarantees that a “coalition of the willing” could provide to Ukraine in this ceasefire are the planned deployment of the UK and France-led Multinational Force Ukraine (MNF-U) and a US-led verification mechanism, both of which have so far been only vaguely defined. Moreover, in the context of the second Trump administration’s mercurial positions on NATO, continued concerns about European militaries’ combat readiness, and the European coalition’s likely concession to cap on the size of Ukraine’s peacetime forces, the planned MNF-U looks unprepared to shoulder the responsibilities of deterrence, and more worryingly, the potential consequences of the ceasefire collapsing.
However, the cap that Ukraine and its European allies are conceding for this ceasefire could in fact be a major accelerant for the modernization of European defences. This is because Ukrainian frontline veterans can still transfer their hard-earned expertise in modern warfare to the MNF-U by joining private military and security companies (PMSCs) following the imposition of a peacetime cap. Consequently, the MNF-U participants must create a framework for the establishment of PMSCs to assist in the training of their forces. This will enable Ukrainian veterans to transfer their battlefield experience to the MNF-U, thereby improving their military readiness and ability to deter Russian aggression.
What Europe lacks, Ukrainian veterans can offer
During the Cold War, European militaries on both sides of the Berlin Wall believed a conflict between NATO and the Warsaw Pact was a reasonable possibility, and accordingly prepared their forces for a peer/near-peer conventional war. Yet, the Cold War’s conclusion saw European militaries instead face both a steep decline in their funding and a proliferation of counterinsurgency and peacekeeping operations globally. As a result, European militaries lost much of their Cold War-era conventional warfare capabilities and became far more reliant on US military support for their own security in Europe.
This hollowing out of Europe’s conventional warfare capabilities would later reduce the utility of NATO’s training for frontline Ukrainian units, as they found that drone, information, electronic, and tunnel warfare were the most relevant forms of warfare on the modern battlefield. Ironically, it is now the European coalition that would benefit from drawing upon Ukrainian veterans’ combat experience here, especially in combined arms operations, as they pursue their rearmament.
To their credit, the European coalition is increasingly aware of these shortcomings in its own defences, and likewise already taking steps to address them. Notably, Poland has taken a leading role here by requesting Ukrainian expertise in the establishment of Europe’s drone wall, with other eastern flank states expected to follow suit. Such measures must go far beyond drone warfare though, particularly to give the MNF-U a more credible edge for deterrence.
The PMSC framework that the European coalition needs
The expected capping of Ukraine’s peacetime forces, whether it be 500,000 or 800,000, will reduce the number of actively-serving Ukrainian military personnel available to transfer their knowledge on modern warfare. On the other hand, Ukrainian veterans could just as easily provide the same technical assistance to the MNF-U, provided they did this in their capacity as PMSC staff instead of as active members of the Armed Forces of Ukraine. The European coalition must therefore develop a framework to encourage Ukrainian veterans discharged under a peacetime cap to join European PMSCs to train their military forces.
To start with, European coalition authorities should specify the operational boundaries for training PMSCs operating in their jurisdictions, particularly regarding legal constraints (like international humanitarian law). PMSCs that would employ Ukrainian veterans should thus look to the Montreux Document and International Code of Conduct Association (ICoCA) as foundations for good practices on more established conventional defence practices, with the expectation that they outline similar rules on cyber and information defence practices as well.
Concurrently, EU members of the coalition must use this moment as an opportunity to draw up a formal EU-wide structure to regulate the operation of PMSCs as well. Despite how EU and national authorities have expressed reservations about explicit regulations on PMSC conduct, numerous EU-based PMSCs have participated in illicit activities like arms smuggling and financial fraud. More recent incidents have gone even further, such as collaboration with Chinese industrial interests in the Democratic Republic of the Congo and an attempted coup during the 2024 Romanian presidential election.
To avoid similar malpractices, the EU and the coalition’s European members must harmonize these regulations and implement more oversight on the operations of these PMSCs to ensure they operate within the bounds of European values and interests. The formation of PMSCs for Ukrainian veterans to train European coalition units would be a good catalyst to do so.
As such, the MNF-U should view the expected peacetime cap on Ukraine’s Armed Forces as a catalyst in improving its tactical and on-the-ground capabilities. By transferring their battlefield expertise through PMSC channels, European forces will be better prepared for modern conventional warfare and function as a more reliable deterrent against Russian aggression in Europe. Such a vital opportunity to bolster Europe’s rearmament must not go unnoticed amid ongoing ceasefire negotiations in the Russo-Ukrainian War.