Partners in Peacemaking: How the United States and Europe Can End the War in Ukraine

Liana Fix is a fellow for Europe at the Council on Foreign Relations.

This Ukraine Policy Brief is part of the Council Special Initiative on Securing Ukraine’s Future and the Wachenheim Program on Peace and Security.

Executive Summary

President Donald Trump has promised to end the war in Ukraine within six months of his inauguration. In principle, the United States could negotiate a peace deal with Russia and Ukraine without involving the leaders of Europe (specifically, the European Union and non-EU NATO members). However, by involving European partners in negotiating a cease-fire, the Trump administration can help secure a better deal for the United States. The advantages include keeping U.S. costs down by having Europe take over the lion’s share of the costs for Ukraine’s financial and economic survival through Russian frozen assets, while the United States provides critical weapons transfers; securing an eventual cease-fire through a European peacekeeping force or mission; integrating Ukraine into the West through accelerated EU membership; and giving the United States greater freedom to operate in the Indo-Pacific by persuading the Europe to increase their defense spending.

Ahead of negotiations with Russia, the Trump administration should include its European allies by taking the following steps:

• Develop a unified negotiation position with Ukraine and Europe, as well as a division of labor in talks. This move will prevent Russian attempts at sowing division and increase the costs for Russia if it violates a future cease-fire deal.
• Work with Europe to fully seize its €260 billion of Russian frozen assets and create a vehicle for the short- and long-term needs of Ukraine. This approach will add pressure on Moscow to enter negotiations as it cannot rely on outlasting Kyiv in domestic economic stability.
• Expect Europe to assume responsibility for a durable peace and contribute to securing a cease-fire in Ukraine. This contribution can take different models (from international peacekeeping to a robust monitoring or tripwire mission), depending on the level of U.S. involvement as well as the contours of a cease-fire deal.
• Encourage Europe to set a deadline—e.g., 2030—for Ukraine’s EU membership, and support the EU on domestic reforms in Ukraine. This move will also accelerate internal EU reform, reassure Ukrainians about their future in the West, and deny Russian President Vladimir Putin a geopolitical victory.
• Negotiate a new defense spending goal of 3.5 percent of GDP with European NATO allies and encourage investments in Europe’s defense-industrial base. The United States has to accept that buying exclusively U.S. weapons only makes Europe weaker and more, not less, dependent on the United States for its security.

A New Burden-Sharing Deal in Ukraine

Excluding Europeans from cease-fire negotiations in Ukraine is not in the United States’ interest. If the United States wants a good deal in Ukraine, it needs European buy-in. Europe already shoulders the majority of the burden for Ukraine’s economic and financial survival. According to the Kiel Institute, Europe (including the EU, United Kingdom, Norway, Switzerland, and Iceland) has provided €124.73 billion ($128 billion) to Ukraine in the last three years, compared to €88.33 billion ($90.75 billion) by the United States. Europe thus accounts for 61 percent of financial, humanitarian, and military support to Ukraine.

Yet, despite its already substantial investments, Europe can and should do more. In a new burden-sharing deal, Europe should substantially increase its support and take over the majority of the costs for Ukraine’s economic and financial survival, as well as its reconstruction, while the United States would focus on the critical weapon deliveries that cannot be replaced by Europeans. Europe has neither the defense-industrial base nor the production capacities to sustain the weapons flows that Ukraine needs to repel a renewed Russian attack; only the United States has the capacity to do so. Europe should also take over the coordination of military support for Ukraine in the Ukraine Defense Contact Group, the so-called Ramstein format, which has so far been led by the U.S. secretary of defense.

A substantial increase of support for Ukraine will be challenging for Europeans. Shrinking fiscal space and the rise of populists affect most European countries. The solution, however, is as obvious as the problem: Europe currently sits on an untapped war chest of €260 billion ($267 billion) of frozen Russian central bank assets. So far, only the interest generated by those assets has been used to provide Ukraine with an annual $50 billion loan. However, this is unlikely to be sufficient. European concerns that seizing Russian assets could make the euro less attractive as a reserve currency and as a safe alternative to the dollar are somewhat overstated; demand for euro reserves is static, and the relevant actors will remain reluctant to only rely on dollar reserves. The negative consequences of failing to adequately support Ukraine would be much greater.

The United States should work with Europeans to fully seize the €260 billion and create a vehicle to continuously dispatch to Ukraine the financial means for its short- and long-term needs, especially reconstruction and defense investments. Europe and the United States have the opportunity to implement a new Marshall plan for Ukraine, at zero cost to their taxpayers, and Ukraine can, if necessary, use those funds to buy weapons from producers in the United States and Europe, recycling the money back into the West. There is also an intuitive moral logic to making Russia pay for the destruction it has wrought: those frozen assets are, in a sense, reparations to Ukraine.

Seizing Russia’s frozen assets has two additional advantages. Ahead of negotiations, it would increase U.S. leverage: a continuous, generously resourced lifeline for Ukraine would dispel the notion that Russia can outlast Ukraine in terms of economic stability. Combined with the current woes the Russian economy is facing, it would increase the pressure on Putin to negotiate a way out of the impasse.

Lastly, seizing the assets would also prevent their return to Russia during one of the biannual European Union (EU) votes to extend sanctions, including on the assets. If only one EU country decides just once to block the extension, the assets would be freed and lost, significantly weakening the United States’ negotiating stance and propping up Russia’s ability to prolong the war. This is not something the United States can afford.

On top of the financial support, having Europeans at the table with a unified position will also increase the negotiating leverage of the United States, and any Russian violation will face consequences from all allies. Moreover, presenting a unified front will prevent Russian attempts to sow division.

Securing a Lasting Cease-Fire

Achieving an end to the fighting in Ukraine is an important priority, but it is only the first step. The second step is to turn a cease-fire into a durable peace and to prevent a humiliating, renewed Russian attack during the Trump administration and beyond. The United States should expect Europeans to assume responsibility and contribute to securing a cease-fire in Ukraine. This would lower the risk that the United States remains tied in the conflict and solely responsible for the survival of Ukraine.

Securing a cease-fire can take different forms, depending on the modalities of the deal reached. The first option is an international peacekeeping mission, possibly put together by the United Nations, with a significant European contribution and supported by technical means, due to the length of the frontline. A UN format would include countries from the Global South, which could have a deterring effect, but it would also give Russia significant sway over the proceedings. This could be problematic, as in past monitoring missions—led by the EU and by the Organization for Security and Cooperation in Europe (OSCE) in Georgia and Ukraine—Russia has not complied with the formal agreements and has never allowed monitors on its side of the line. Russia also has continuously attacked or put in danger the personnel of those missions without any accountability.

The second option would be a robust European coalition of the willing, which would deploy European troops in western Ukraine as a tripwire contingent to deter a renewed attack. In such a scenario, Russia would have to expect a fully fledged European (and possibly U.S.) response if those troops were attacked. This option, however, also bears the risk of European-Russian and/or U.S.-Russian escalation. A robust European mission, as floated last year by French President Emmanuel Macron, could require an initial 20,000 to 40,000 troops, and up to 100,000 with rotations and support personnel. Although those forces would draw from NATO’s new defense plans, the security of Europe is arguably better defended in Ukraine than it is on NATO territory.

But a robust European mission will not succeed without U.S. support. The United States should clearly outline its own level of involvement. Questions that need to be answered include if and how much logistical, intelligence, or air support the United States would provide, and the extent to which an attack on the European tripwire contingent would draw in direct U.S. involvement, despite the troops’ position outside of NATO territory and, therefore, Article 5 guarantees. Despite those difficult questions, it is more advantageous for the United States to give Europe significant responsibility for securing a cease-fire, rather than doing it alone or risking the return of war within a few years’ time.

Lastly, a combination of international peacekeeping and a robust European mission has also been proposed by European military expert Franz-Stefan Gady: “Traditional peacekeepers, ideally from countries of the Global South, could directly patrol a demilitarized zone along the cease-fire line, and a robust European rapid-reaction force could be stationed further back inside unoccupied Ukraine.” This would have the advantage of both deterring a renewed Russian attack and minimizing the risks of escalation.

A Democratic Ukraine Anchored in the West

To anchor Ukraine firmly in the democratic West and to ensure its domestic stability, the United States should encourage Europe to accelerate Ukraine’s integration into the European Union and set a deadline for finalizing negotiations. Of course, EU membership is not a suitable replacement for NATO membership or any other bilateral or multilateral security guarantees. The EU’s Article 42.7 mutual assistance clause is nowhere near as strong as NATO’s Article 5 collective defense, which is why EU members Finland and Sweden have decided to join NATO. Yet, EU membership for Ukraine is the best path available at the moment—in lieu of NATO membership in the short term—to reassure Ukraine of its Western perspective, to fuel its resilience, encourage reforms, and strengthen its democratic aspirations. It will also help to prevent the emergence of Ukrainian revanchism, which both former Ukrainian Foreign Minister Dmytro Kuleba and former U.S. Secretary of State Henry Kissinger have warned against. In addition, Washington should support Brussels in demanding internal reforms from Kyiv to prevent democratic backsliding, as in the case of Georgia.

Europe has already agreed to start negotiations with Ukraine in June 2024, but those are much more technical and substantial than NATO accession. Ukraine will have to adopt the entire body of law—the acquis—of the EU, consisting of thirty-five chapters, and pursue deep domestic reforms in the process. Meanwhile, the EU will have to embark on ambitious internal reforms, too, to accommodate a country the size of Ukraine and to prevent paralysis in an enlarged EU, especially if more countries—the Western Balkans and Moldova—join at the same time. To prevent a failed accession as with Turkey, the United States should encourage the EU to accelerate Ukraine’s integration where possible.

Europeans could point to the technical nature of the process, which makes acceleration difficult. However, there is a strong geopolitical interest behind Ukraine’s accession, which has already allowed the EU to fast track its invitation to Ukraine. EU membership will also make it attractive for Ukrainian refugees to return and confirm that Ukraine has a home in the West—denying Putin his ambition to subjugate the country.

The Future of Europe’s Defense

All of the U.S. interests outlined so far, from creating a new deal for transatlantic burden-sharing on Ukraine to securing a durable peace and anchoring Ukraine in the West, will require Europe to do more for its own defense. This would signal to Russia, in the context of Ukraine negotiations, that Europeans are serious about Ukraine’s defense, as well as their own, and that the costs of a renewed adventure in Ukraine or beyond would be too high. The United States should negotiate with NATO allies to set a higher target for defense spending, for example 3.5 percent of gross domestic product (GDP).

For defense investments, and for the fiscal space to increase spending, Europeans will have to develop joint means of action, such as joint EU debt for the purpose of defense. Already, there have been valuable discussions about using EU cohesion funds for defense purposes or building a defense bank. Internal divisions within the EU over those ideas will require compromise, and the United States should encourage action.

Increasing spending is only part of the problem, however. Allies also need to use that money wisely. NATO’s new defense plans demand swift and thorough implementation. At the same time, Europe needs to invest in its own defense-industrial base. Buying exclusively from the United States weakens both the United States and Europe by limiting a swift expansion of production capacities. It also makes Europe more dependent on the United States for its own security, to the detriment of U.S. interests globally.

With its own strong industrial base, Europe can begin to produce its own strategic capabilities for European security, allowing the United States to shift some of its resources to other theaters and prioritize deterring China in the Indo-Pacific, a costly and demanding challenge. The United States would still remain committed conventionally and through its nuclear deterrent to Europe, but a larger part of the conventional burden would be shouldered by Europeans. Such a transatlantic bargain would benefit both sides and help solve the free-riding problem criticized repeatedly by President Trump.

Conclusion

To secure the best possible outcome in Ukraine cease-fire negotiations, the United States should work with its European partners, rather than go over their heads. A peace deal with European buy-in would be a better and less costly peace deal for the United States than without Europe. Involving Europe will strengthen the United States’ negotiating position, reduce the U.S. burden in Europe, anchor Ukraine firmly in the Western democratic community, and build a more durable peace on the continent. As heavily vested parties in the war, Europeans should assume responsibility for securing a cease-fire. Without such security guarantees, the Trump administration risks replicating the Afghanistan debacle if Russia decides to attempt another attack on Ukraine in the next few years. This scenario should be avoided at all costs.

This work represents the views and opinions solely of the author. The Council on Foreign Relations is an independent, nonpartisan membership organization, think tank, and publisher, and takes no institutional positions on matters of policy.