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IBRU: Centre for Borders Research

Boundary news

Boundary news Headlines

Croatia and Slovenia sign boundary arbitration agreement

(5 November 2009)

On 4 November 2009 the prime ministers of Croatia and Slovenia, Jadranka Kosor and Borut Pahor, signed an agreement on boundary arbitration that was witnessed by Sweden's prime minister Fredrik Reinfeldt, the current president of the European Union. After some eighteen years of negotiations, Croatia and Slovenia have agreed to set up an arbitral tribunal to define the full course of their land and maritime boundaries. The two parties have also asked the arbitral tribunal to identify "Slovenia's junction to the High Seas" and "the regime for the use of the relevant maritime area."

According to the agreement, the arbitral tribunal will be composed of five judges. Three will be chosen jointly by the parties from a list of candidates supplied by the President of the European Commission and the official responsible for EU enlargement, and the two parties will then appoint one additional judge each. The agreement states that the tribunal will base its decision on international law, as well as the principles of equity and good neighbourliness in order to "achieve a fair and just result by taking into account all relevant circumstance." The critical date is specified as 25 June 1991 which means that no evidence after that date will be applicable. In addition, the agreement specifies that none of the material presented by either state in their accession negotiations with the EU, such as documents, reports or maps, can be used in support of their claims. Most crucially, the arbitration procedure can only begin when Croatia signs its accession treaty to the European Union, a move that has hitherto been blocked by Slovenia as a result of the boundary dispute but which is widely considered already to be at an advanced stages of preparation. As part of the agreement, Slovenia agreed to lift its reservations concerning Croatia’s accession.

The timeline for the arbitration appears quite short, as both parties have to submit their written memorials within twelve months of the commencement of the arbitration. Both parties will also be able to respond to the opposing memorial within a timeframe set by the tribunal. The two parties will share the costs of the tribunal which will sit in Brussels, a choice which emphasises the EU’s engagement in resolving the dispute.

The arbitration agreement must be submitted to the respective legislatures for ratification within the next two weeks, which means that opposition groups in one or both states could still derail the agreement. However, the agreement seems tailored to the key political demands of both states. The scope of the dispute, including the unorthodox request to define Slovenia’s ‘junction’ with the high seas and define a relevant maritime regime, appears to reflect Slovenia’s maritime concerns. On the other hand, the fact that the arbitration can only begin immediately after Croatia’s accession to the EU, and that Slovenia agrees to lift its reservations, facilitates one of Croatia’s central political goals.

Sources: ‘Zagreb and Ljubljana sign arbitration agreement’ Europolitics, 5 November 2009; ‘Slovenia and Croatia Sign Arbitration Agreement’ STA, Slovenska Tiskovna Agencija, 4 November 2009; ‘Tribunal shall determine Slovenia's junction to high sea’ Emportal STA, 31 October 2009.