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".
Croats of Bosnia and Herzegovina
At the beginning of the Bosnian War, Bosnian Croats were first to organize themselves, especially Croats in western Herzegovina who were already armed. At the end of May 1992, Croats launched a counter-offensive, liberating Mostar after a month of fighting. Also, in central Bosnia and Posavina, Croatian forces stopped the Serbian advance, and in some places they repelled the enemy. On 16 June 1992, President of Croatia, Franjo Tuđman and President of Bosnia and Herzegovina, Alija Izetbegović signed an alliance according to which, Bosnia and Herzegovina legalized the activity of Croatian Army and Croatian Defence Council on its territory. Bosnian Croat political leadership and the leadership of Croatia urged Izetbegović to form a confederation between Bosnia and Herzegovina and Croatia, but Izetbegović denied this since he tried to represent Serbian interests as well as those of Bosniaks and Croats. The Bosnian Croat leadership was irritated by Izetbegović's neutrality, so Mate Boban threatened to pull back the HVO from actions in Bosnia. Since the UN implemented embargo to Bosnia and Herzegovina on the import of arms, Bosniak and Croat forces had difficulties fighting Serbian units, which were supplied with arms from the Middle East, just before the outbreak of war. However, after Croat and Bosniak forces reorganized in late May 1992, the Serbian advance was halted and their forces mostly remained in their positions during the war. The tensions between Croats and Bosniaks started on 19 June 1992, but the real war began in October.