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".
Battle of Šibenik
After two unsuccessful attempts by Serbia, supported by Montenegro and Serbia's provinces of Vojvodina and Kosovo, to obtain the Yugoslav Presidency's approval of a JNA operation to disarm Croatian security forces in January 1991, and a bloodless skirmish between Serb insurgents and Croatian special police in March, the JNA itself, supported by Serbia and its allies, asked the federal Presidency to give it wartime authorities and declare a state of emergency. The request was denied on 15 March, and the JNA came under control of Serbian President Slobodan Milošević. Milošević, preferring a campaign to expand Serbia rather than preservation of Yugoslavia, publicly threatened to replace the JNA with a Serbian army and declared that he no longer recognised the authority of the federal Presidency. The threat caused the JNA to gradually abandon plans to preserve Yugoslavia in favour of expansion of Serbia. By the end of the month, the conflict had escalated to the first fatalities. The JNA stepped in, supporting the insurgents, and preventing Croatian police from intervening. In early April, leaders of the Serb revolt in Croatia declared their intention of integration of the area under their control, viewed by the Government of Croatia as a breakaway region with Serbia.