ISSUE: 4/2025
- Volume 29
- Number 4
- 2025
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Studia Europejskie –
Studies in European Affairs
ISSN: 1428-149X
e-ISSN: 2719-3780
License
Articles published in the journal are under a Creative Commons Attribution – Non Commercial – No Derivatives 4.0 International License
Publication co-financed by Ministry of Science and Higher Education pursuant to the Regulation of the Minister of Education and Science of 3 August 2021 (Journal of Laws of 2021, item 1514) on the “Development of Scientific Journals” programme.
Publikacja dofinansowana przez Ministerstwo Nauki i Szkolnictwa Wyższego na podstawie rozporządzenia Ministra Edukacji i Nauki z 3 sierpnia 2021 r. (Dz. U. z 2021 r. poz. 1514) w sprawie programu „Rozwój czasopism naukowych”.
Publication co-financed by the University of Warsaw within the “Excellence Initiative – Research University” programme.
Czasopismo otrzymało dofinasowanie w ramach Programu „Inicjatywa Doskonałości – Uczelnia Badawcza”.
Improving the EU’s Readiness to Admit Ukraine Without Amending the Lisbon Treaty
Abstract
In the unprecedented circumstances of the full-scale war in Ukraine, the country’s accession to the European Union (EU) has come to be viewed as a geopolitical imperative. However, despite renewed political commitment to enlargement, the Union remains poorly equipped to admit new members without jeopardising its internal cohesion and functionality. This article examines how the EU can enhance its institutional readiness to integrate Ukraine without amending the Lisbon Treaty. It identifies four complementary reforms that can strengthen the Union’s decision-making and enforcement capacities: (a) broader use of Qualified Majority Voting (QMV); (b) activation of the passerelle clauses as a legal bridge toward flexibility; (c) strategic use of constructive abstention to preserve unity in the Common Foreign and Security Policy (CFSP); and (d) development of a cooperative enforcement model to improve implementation of EU legislation. By linking these mechanisms to the current debate on enlargement and governance, the article demonstrates that meaningful institutional adjustment is possible within the existing Treaty framework. It argues that such reforms would not only prepare the EU for Ukraine’s accession but also strengthen the Union’s overall legal coherence, external credibility, and rule-of-law resilience. To conclude, this paper advocates that the momentum created by Ukraine’s membership application should be seized upon to build a more responsive, credible, and strategically autonomous Union – one capable of deepening its integration while widening its membership.
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European Commission (2025) Implementing EU Law. Available at: https://commission.europa.eu/law/application-eu-law/implementing-eu-law_en (Access 30.10.2025).
European Council (2022) Doorstep of President Charles Michel Ahead of the European Council and the EU–Western Balkans Leaders’ Meeting. Statements and Remarks.
European Parliament (2024) Resolution of 11 July 2023 on the Implementation of the “Passerelle” Clauses in the EU Treaties (2022/2142(INI)).C/2024/3996.
Fabbrini, F. (2025) “The Impact of the War in Ukraine on the Enlargement of the European Union: Securing the Blessings of Liberty and Its Challenges”, International and Comparative Law Quarterly. Vol. 74(1), pp. 123–146. DOI: 10.1017/S0020589325000107.
Franco-German Working Group on EU Institutional Reform (2023) Sailing on High Seas: Reforming and Enlarging the EU for the 21st Century. Available at: https://www.auswaertiges-amt.de/blob/2617322/4d0e0010ffcd8c0079e21329bbbb3332/230919-rfaa-deu-fra-bericht-data.pdf (Access 30.10.2025).
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Kennedy, P. (1987) The Rise and Fall of the Great Powers: Economic Change and Military Conflict from 1500 to 2000. Random House.
Kotanidis, S. (2020) Passerelle Clauses in the EU Treaties: Opportunities for More Flexible Supranational Decision-Making. European Parliamentary Research Service.
DOI: 10.33067/SE.4.2025.6
Language: English
Pages: 125-139
How to Cite:
Harvard
Dionysiou, E. (2025) "Improving the EU’s Readiness to Admit Ukraine Without Amending the Lisbon Treaty". Studia Europejskie – Studies in European Affairs, 4/2025, pp. 125-139. DOI: 10.33067/SE.4.2025.6