PUBLICATION: Policy brief

Bilateral disputes and EU enlargement: A Consensual Divorce

Bilateral disputes between European Union member states and candidate countries are one of the key obstacles to EU enlargement. They have been plaguing the EU accession process ever since the breakup of Yugoslavia and the subsequent border dispute between EU member Slovenia and candidate country Croatia which then ensued. More recently we have the case of North Macedonia. It became a candidate country in 2005 but ever since, its accession negotiations have been bogged down by endless bilateral disputes.

While the case of North Macedonia and its decades-long conflicts with Greece and Bulgaria are the most well-known of such cases, they are not the only ones.

Even when a candidate country meets the criteria to progress in EU accession talks, bilateral disputes can delay it for years or even decades as in the case of North Macedonia. In this way, such disputes present a serious challenge to the credibility of the EU enlargement process. In the context of the war in Ukraine, as we have seen with regard to the policies of Viktor Orbán’s Hungary towards Ukraine, invoking bilateral disputes can seriously challenge the geopolitical orientation and the security of the entire Union.

On the legal side, since most of these issues fall outside the scope of the EU law and are not covered by the accession criteria, there is a need to think of an institutional mechanism to deal with bilateral disputes. Enlargement policy does not offer an appropriate platform for settlement of bilateral disputes, especially for those that fall outside the EU law. Hence, these issues should be addressed via the international legal dispute resolution toolbox and thus be subjects of separate processes. The EU’s role however cannot be passive. It should invest efforts in these processes in order for them to be mutually reinforcing and so that the accession process has a mollifying rather than tension amplifying effect on the issue.

In this policy brief we suggest ways how to operationalise this proposal. First, we describe different types of vertical bilateral disputes (the ones that include asymmetrical relations) between EU members and Western Balkan candidate countries, then we outline international mechanisms to resolve them, and finally we propose an institutional architecture to remove bilateral disputes that fall outside of the scope of the Copenhagen criteria and the EU acquis from the purview of EU accession talks.

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