Can the French Electorate Derail the EU’s Next Enlargement?

Matthias Waechter I David Waechter
1 October 2026 | Issue No. 197

Matthias Waechter is Director General of CIFE.

David Waechter holds a Master degree in Comparative and Constitutional Law from University Paris X Nanterre. He pursues postgraduate studies at Ecole normale supérieure in Paris.

France’s political leaders have historically played a highly constructive role in the European integration process, making the country into one of its major agenda-setters. It was forward-thinking French statesmen such as Robert Schuman and Jean Monnet who invented in 1950 the method of supranationality. It was due to the initiative of French President Valéry Giscard d’Estaing that the European Council, the regular meeting of heads of state and government, was created. France under François Mitterrand was instrumental in making the turning point of 1989 into a decisive moment of European integration, by coupling German unification with the fulfilment of the monetary union. However, paradoxically has France also been a member state blocking major advancements of the integration process, for instance when President Charles de Gaulle prevented not only the introduction of qualified majority decisions, but also the first enlargement of the community. Also, major projects originating in France have later failed precisely because of that country. Thus, the French project of a European Defence Community was buried in 1954, because it didn’t find a majority in the French National Assembly. Similarly, the Constitutional Treaty of the EU, elaborated by a convention under the leadership of former French President Valéry Giscard d’Estaing, could not be ratified because of its refusal in the French referendum of 2005. 

Thus, the question arises what the role of France in the upcoming enlargements of the European Union will be. Since the Russian full-scale invasion of Ukraine, there has been a new dynamic in EU enlargement. Not only have countries such as Ukraine, Moldova, and Georgia become candidate countries, also the accession process to the Western Balkan countries, which previously had slowed down, has gained significant momentum. According to the projects of the European Commission, Montenegro should become by 2028 the 28th member state of the EU, followed soon by Albania. Will France be a stumbling block in admitting Montenegro and Albania to the EU? The question is particularly relevant, as a constitutional provision makes it more difficult to ratify future EU accessions in France than in other member states. France is the only member state where a popular referendum is the default procedure for each future EU enlargement. Thus, will it be up to the French population to ultimately decide whether the Western Balkan countries, Ukraine and Moldova can become EU members? What are alternative scenarios? Our paper first looks at the historical origins of this constitutional provision and the way it has further evolved. We will then examine potential scenarios for the ratification of a future EU enlargement in France and finish with some recommendations. 

Why is there a French constitutional provision on ratifying future enlargements by referendum?

Originally, the Constitution of the Fifth Republic did not contain any provisions on how future enlargements of the European community should be dealt with. When it came to the first enlargement to the United Kingdom, Ireland and Denmark, President Georges Pompidou called a referendum, without being obliged to do it. All further accessions were ratified by a parliamentary procedure. The idea of making referendums mandatory for further enlargements emerged only in 2004/05 from the conjunction of two political debates: The controversy over Turkey’s possible accession to the EU and the forthcoming French referendum on the constitutional treaty of the European Union. The prospect of future Turkish EU membership provoked hostile reactions among the French electorate and especially right-wing political parties. They instrumentalized the debate on ratifying the constitutional treaty and made it seem that voting “No” to the treaty would also prevent Turkey from acceding to the EU. To avoid that the Turkish issue would further poison the debate on the constitutional treaty, President Chirac made a consequential promise: The French would have their say on the accession of Turkey to the EU, not only through their parliamentary representatives, but directly through a referendum.¹

This commitment would find its legal translation in the constitutional reform n°2005-204, which came into effect on 1^st March 2005². Introduced after the ruling of the Constitutional Council on the Treaty establishing a Constitution for Europe³, the amendment aimed at clearing the constitutional hurdles that prevented the potential entry into force of the treaty. At the same time, it also added, through a new article 88-5 of the Constitution, the so-called “Turkish clause” that requires “any bill authorising the ratification of a treaty relating to a State’s accession to the European Union” to be put “to a referendum by the President of the Republic”. To specifically single out Turkey, this clause would not apply to “accessions following an intergovernmental conference (…) decided before the 1st of July 2004”, thus excluding the enlargement to Bulgaria, Romania and Croatia, but applying to any other European country whose negotiations would have begun after this date. 

In the wake of the failure of the Treaty establishing a Constitution for Europe due partly to the “No” vote in the French referendum, many French politicians felt that the clause had outlived its purpose and placed unnecessary constraints on EU enlargement, in a time where the European Union needed new impetus. In January 2008, Jean-Pierre Jouyet, Secretary of State for European Affairs under President Nicolas Sarkozy, pushed for the suppression of the article, arguing that it would be “inappropriate, cumbersome and damaging to international confidence” if France was to systematically resort to a referendum for every enlargement⁴. Thus, the Balladur committee, which Sarkozy had established to elaborate recommendations for the “modernisation of the institutions” proposed to abolish the “referendum lock” and to replace it by an enhanced parliamentary procedure. The adopted amendment (constitutional reform 2008-724 of 23^rd July 2008⁵) gives a discretionary choice to the President for any ratification of an EU accession: He or she can either trigger a referendum or use the parliamentary procedure. However, unlike any other treaty where a simple majority of both chambers is sufficient, the parliamentary approval of an EU accession treaty needs a qualified majority equivalent to that required for a constitutional revision:⁶  the treaty must be adopted in identical terms by both chambers, before being approved by the 3/5 of the deputies of Congress (which assembles all the deputies of the National Assembly and the Senate). 

Could a future EU enlargement be ratified by France in the coming years? 

For France to approve any further EU enlargement, one of the two procedures of article 88-5 of the Constitution must succeed. Considering first the option of the referendum, this path appears highly risky considering the state of French public opinion. While the French generally feel attached to the EU (55%)⁷, they are, according to the latest Eurobarometer poll on the question, among all member states the most opposed to accepting new countries into the European Union: only 40% of the respondents are in favour, while 51% oppose it. When looking closer at the Western Balkans countries who will be most likely the next to enter the Union, 40% are in favour of Montenegro, and only 37% view the accession of Albania favourably.⁸ One could argue that a possible referendum might only motivate those being in favour to cast their vote and that, since there is no quorum, also a minority of voters could bring about a positive result. However, a referendum in France always poses the risk of being turned into a plebiscite about the incumbent government. Thus, the referendum on the European Constitution in 2005 failed in part because it was perceived by the French electorate as a plebiscite for or against the ruling president, Jacques Chirac. Of course, current polls don’t allow to project the eventual result of a referendum regarding the accession of a particular state such as Montenegro. They do, however, show a consistent anti-enlargement tendency in the French population, which would be a heavy hurdle in any accession campaign, and could, just like in 2005, break the political momentum of the European Union. 

Considering these obstacles, the parliamentary option could seem like a more secure way to ensure the French approval to EU accession. However, in the current situation, a parliamentary approval of accession is far from guaranteed. If we take the current National Assembly as an indicator, the coalition around President Emmanuel Macron can garner the support of about 233 deputies out of 577 (40% of the National Assembly). Securing the approval of parties not supporting the president is currently not easy, as the public could interpret it as an endorsement of the government, which would be politically costly. 

As the ratification procedure of the accession treaty with Montenegro should take place in 2027, the viability of the parliamentary option depends strongly on the results of the French presidential elections of April and May 2027, and the probable legislative elections that will ensue. Eurosceptic candidates are polling highly in the surveys, such as Jean-Luc Mélenchon (around 15%) and Marine Le Pen (up to 35%). If the Rassemblement national wins the election, any new EU accession would be blocked by the president, as all international treaties must be ratified by him or her. However, even if a candidate favourable to EU enlargement wins, it would still be necessary for him to obtain a qualified majority in the National Assembly. Considering the current political situation in France, this is far from being guaranteed as the legislative elections could well reproduce the current tripartition between left, centre-right and far-right movements.

What can be done to make a French “Yes” to further EU enlargement possible?

To make a French endorsement of future accessions possible, both public opinion and political elites need to shift from enlargement skepticism to a positive view of a bigger union. For this to happen, two interrelated problems need to be tackled: The lack of knowledge about enlargement and the Western Balkans countries and the lack of a positive narrative of enlargement. For many French citizens, EU enlargement remains a policy field about which they know too little. According to a 2025 opinion poll, 74% of respondents feel not well enough informed about EU accession.⁹ When we look at enlargement narratives, negative representations of the process have largely dominated public discourse in France. The Eastern enlargement of 2004/7 was seen by many French as a process with predominantly negative consequences for the population. Outsourcing to new member states entailing deindustrialisation in France were among the perceived downsides of enlargement. French citizens feared immigration from the new member states and accused them of unfair competition. The figure of the “Polish plumber”, coming to France offering his services under favourable Polish working conditions and squeezing the French plumber out of business, gained legendary status.¹⁰

From the side of the political elites, not enough was done to counter these negative narratives and insist on the geopolitical advantages of enlargement, which has helped turning Central Europe into a space of security, democracy, stability and common values. In the wake of the 2004/07 accessions, French politicians began to see enlargement more as a “zero-sum game”, which entailed opportunities for Germany as the economic powerhouse deploying its sway in its Eastern neighbourhood and drawbacks for France seeing its influence diminishing. In his first term, President Emmanuel Macron departed from the widely shared vision which sees the widening of the European Union as complementary with its deepening. He gave precedence to the latter and demanded that the EU should first reform and strengthen internally before admitting new members, a logic which led him to blocking the opening of accession negotiations with Albania and North Macedonia in 2019.

The French approach has changed since the full-scale attack of Russia on Ukraine in 2022. Among decision-makers, the awareness has returned that enlargement is essentially a geopolitical project and that the risks of non-accession can be significant, as it opens the door for rivalling powers such as China and Russia. France now endorses enlargement to the six Western Balkan countries as a “strategic necessity in the current geopolitical context”, as the spokesperson of the Quai d’Orsay said in a press conference in May 2026.¹¹ At the same time, the French government insists on being extremely vigilant concerning reforms in the candidate countries, on introducing safeguard clauses and transitional periods when proceeding towards accession treaties, in order to reassure French citizens and public opinion.¹² It thus appears that French decision-makers are aware of the risk that French public opinion poses to future enlargements, but so far no visible government efforts have been deployed to convince the citizens that an enlarged EU is an asset for all of us. A comprehensive, nation-wide campaign is needed which anticipates the upcoming ratification procedures by transmitting a narrative which poses enlargement in the general context of our times: An EU faced with growing economic competition, an expansionist Eastern neighbour, and an increasingly unreliable transatlantic protector, while slowly emerging as an autonomous geopolitical actor with a common security identity. A bigger EU is also a stronger EU in a ferocious world.

References

¹ Announcement made on a press conference on October 1st 2004 in Strasbourg
² Constitutional Law No. 2005-204 of 1 March 2005 amending Title XV of the Constitution, Journal officiel de la République française [JORF], No. 51, 2 March 2005 (Fr.)
³ French Constitutional Council, Decision No. 2004-505 DC of 19 November 2004, Treaty Establishing a Constitution for Europe
⁴ Jean-Pierre Jouyet, “Excerpts from an Interview,” Secretary of State for European Affairs, Vie publique (French Government)
⁵ Constitutional Law No. 2008-724 of 23 July 2008 on the Modernisation of the Institutions of the Fifth Republic, Journal officiel de la République française [JORF], No. 0171, 24 July 2008 (Fr.)
⁶ The procedure for a constitutional reform is detailed in article 89 of the Constitution
⁷ European Commission, The Latest Eurobarometer Survey Confirms French Ambivalence Towards the EU, 15 December 2025
⁸ European Parliament, Plenary Insights: Public Opinion at a Glance, April 2026
⁹ EU Commission Representation in France, Sondage Eurobaromètre : les jeunes Européens comptent parmi les plus fervents partisans de l’élargissement de l’UE
¹⁰ Cf. Christian Lesquesne, La France dans la nouvelle Europe. Assumer le changement d’échelle, Paris 2008
¹¹ Ministère de l’Europe et des Affaires étrangères : Conférence de presse du porte-parole du 28 mai 2026
¹² Cf. French Minister for European Affairs Benjamin Haddad in a meeting of the French Senate on 15 June 2026