Maryna Rabinovych argues that Russia’s invasion of Ukraine reshaped EU enlargement dynamics, creating both pressure and opportunity. To sustain momentum, the EU needs a strategic vision and transparent policies. By harnessing wartime spillover effects, the EU can transform reactive measures into structured accession pathways for Ukraine and Moldova
In times of crises, scholars and policy analysts tend to concentrate on fast, high-stakes decisions by governments or specific leaders. The literature on the EU’s response to Russia’s invasion of Ukraine followed this pattern. Much of the focus was on member states’ foreign policy coordination on major issues such as sanctions against Russia or the granting of candidate-country status to Ukraine and Moldova.
Yet the Russia-Ukraine war has also brought EU integration pressures beyond the realm of high politics into sharp focus. Neofunctionalism suggests that crises often produce spillover effects which can deepen and broaden integration. This is evident in Ukraine’s EU Single Market integration, rooted in prewar ties under the EU-Ukraine Association Agreement and accelerated by wartime disruptions. Analysis of the war’s spillover effects reveals that Ukraine, and potentially Moldova, are already moving closer to the EU well before formal enlargement has taken place.
Ukraine, and potentially Moldova, are already moving closer to the EU well before formal enlargement has taken place
Spillover effects are generated when policy change in one sector (in this instance, a crisis response) extends to others. Such effects are often promoted by supranational interest groups and businesses, or by EU institutions such as the Commission or Parliament.
One example is the EU’s Solidarity Lanes initiative, launched to counter Russia’s blockade of Ukraine’s maritime exports. This ‘functional spillover’ has supported Ukraine but also expanded integration with Moldova. The initiative includes both countries in plans to revise its trans-European transport networks (TEN-T). It also grants them access to new infrastructure funding opportunities through the Connecting Europe Facility (CEF).
‘Geographical spillover’ reflects the EU’s growing security interdependence with Ukraine. The EU has urged Ukraine to engage in competition with Russia ‘over the European political, economic and security order’. Ukraine’s Single Market integration has spurred progress in areas such as industrial product conformity assessments, which were previously stalled.
Increased collaboration between EU and Ukrainian stakeholders has deepened institutional ties, reinforcing Ukraine's EU integration
Wartime pressures have also catalysed ‘political’ and ‘cultivated’ spillovers. Increased collaboration between EU and Ukrainian stakeholders has deepened institutional ties. The European Commission’s active role in shaping responses, meanwhile, underscores the influence of supranational actors. Empirical evidence from relevant Commission Directorates-General suggests their exchange with Ukrainian colleagues and centrality in coping with functional pressures, e.g. through the work on the Solidarity Lanes proposal. Together, these interconnected logics reveal a complementary process that reinforces Ukraine’s EU integration.
As the Russia-Ukraine war enters its third year, maintaining momentum for enlargement is becoming increasingly difficult. The waning sense of urgency, coupled with domestic pressures in member states, has created space for countervailing forces. These include opposition from certain governments and subnational actors — including farmers in the EU troubled by grain exports — which can dilute the constructive effects of wartime spillovers.
As the war enters its third year, it becomes harder to maintain momentum for enlargement — and this creates space for countervailing forces
Two critical actions will build on the progress already achieved, and ensure Ukrainian and Moldovan accession remains on track. Rethinking the enlargement process is a strategic necessity, as is organising a staged accession process that balances immediate support with long-term commitments:
As Veronica Anghel argues in her foundational blog for this series, 'enlargement is not a gamble but a strategic necessity'. She highlights the dire consequences of inaction, such as ongoing instability at the EU’s borders, and reduced strategic autonomy. To add a positive dimension, it is essential to underscore both the tangible gains — such as an expanded EU Single Market — and more intangible achievements, like heightened public trust and support for European integration within candidate countries. Preserving these commitments is essential for the EU’s credibility, particularly given the strengthening of people-to-people ties with Ukraine since the war began.
Building on wartime spillover effects requires embedding them into clear, transparent, and predictable policy frameworks for Ukraine’s and Moldova’s EU accession. Many wartime developments — from launching Solidarity Lanes to forming new administrative networks — have already drawn these countries closer to the EU. Realising their full potential calls for a staged accession process that balances immediate support with long-term commitments. This could begin with economic and infrastructural cooperation, followed by deeper political and institutional integration as reforms advance. A structured, transparent approach will solidify current achievements and ensure that accession for Ukraine and Moldova remains sustainable, predictable, and comprehensible to citizens across the EU and the candidate countries.
