Is EU enlargement merit-based or politically driven?
Our research suggests both. In a new paper, we examine the degree to which European Union candidate countries have implemented the required reforms on EU common rights and obligations – the acquis communautaire – and the progress of accession negotiations.
Montenegro, the leader in acquis adoption, could feasibly complete accession negotiations by the end of 2026 or early 2027. Albania, less advanced in reforms but making systematic progress, wants to conclude negotiations by the end of 2027. Moldova and Ukraine, which recently opened negotiations on Cluster 1 (‘Fundamentals’, including democratic governance and judicial independence rules) of the acquis, have much further to go than most of their Western Balkan peers, though Moldova has made substantial progress since 2023.
Serbia, which had a similar reform record to Montenegro in 2020, has since seen progress stall or even reverse. Democratic backsliding, rule of law concerns and the lack of alignment with the EU’s Common Foreign and Security Policy have caused accession negotiations to stagnate since December 2021.
Many candidates thus see accession negotiations advance or pause in line with their progress on acquis adoption – but not always. North Macedonia, a candidate country since December 2005 with a relatively good reform record, has been unable to move beyond acquis screening; first Greece and then Bulgaria blocked opening accession negotiations based on historical issues unrelated to acquis reforms.
Greater integration and EU institutional development since previous enlargements have made the process of adopting the acquis more difficult than ever before. This increases the importance of ensuring that accession negotiations are merit-based and shielded from incumbent EU countries’ attempts to use them for domestic political purposes or in bilateral disputes with candidates on issues unrelated to accession. Eliminating the unanimity requirement in enlargement-related decisions in favour of qualified majority voting would be a start.
Stay tuned for the upcoming paper, ‘Progress on accession-related reforms by EU candidate countries', by Marek Dabrowski and Maria Catarina Louro
The Why Axis is a weekly newsletter distributed by Bruegel, bringing you the latest research on European economic policy.
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