Arbitration Commission of the Peace Conference on Yugoslavia
On 20 November 1991 Lord Carrington asked: "Can the internal boundaries between Croatia and Serbia and between Bosnia and Herzegovina and Serbia be regarded as frontiers in terms of public international law?" Applying the principle of "uti possidetis juris", the commission concluded on 11 January 1992, "The boundaries between Croatia and Serbia, between Bosnia and Herzegovina and Serbia, and possibly other adjacent independent states may not be altered except by agreement freely arrived at... Except where otherwise agreed, the former boundaries become frontiers protected by international law".
Croatia
Since 2003, Croatian foreign policy has focused on achieving the strategic goal of becoming a member state of the European Union (EU). In December 2011, Croatia completed the EU accession negotiations and signed an EU accession treaty on 9 December 2011. Croatia joined the European Union on 1 July 2013 marking the end of a process started in 2001 by signing of the Stabilisation and Association Agreement and Croatian application for the EU membership in 2003. A recurring obstacle to the negotiations was Croatia's ICTY co-operation record and Slovenian blocking of the negotiations because of Croatia–Slovenia border disputes. The latter should be resolved through an Arbitration Agreement of 4 November 2009, approved by national parliaments and a referendum in Slovenia., but due to the events during arbitration Croatia does not accept results. As of 2019, Croatia has unsolved border issues with all neighbouring former Yugoslav countries (Slovenia, Serbia, Bosnia and Herzegovina, Montenegro).