Kostic, a Montenegrin who served as vice-president of the Yugoslav federation in 1991/92, confirmed in his testimony that "Milosevic and the Serbian leadership at the time undoubtedly wanted to preserve Yugoslavia". He added that he himself found it hard to come to terms with the fact that Yugoslavia did not exist anymore.
At the start of his testimony at the tribunal on 4 October 2002, Mesic said that Milosevic had told him that "all Serbs will live in a single state" and pointed out that Milosevic "led the world to believe he was fighting for Yugoslavia, although he was doing everything to destroy it."
Mesic confirmed the allegations from the indictment that Milosevic and the Serbian leadership, with the help of the Yugoslav People's Army (JNA) and Serb leaders in Croatia and Bosnia-Herzegovina, were implementing a plan by Serbia to expand territorially by occupying large areas of Croatia and Bosnia-Herzegovina in order to incorporate them into a single Serb-dominated state.
Answering questions put by Milosevic, who conducts his own defence, Kostic denied the alleged existence of the plan to create a Greater Serbia, claiming that there was actually a plan for "the violent secession of Slovenia, Croatia, and Bosnia-Herzegovina."
"Conflicts began with unilateral, secessionist actions by Slovenia and Croatia to overthrow the constitutional order of the Socialist Federal Republic of Yugoslavia," the witness said, adding that in June 1991 Slovenia took control of border crossings, which he said prompted Federal Prime Minister Ante Markovic to order the JNA to intervene, while Croatia announced it no longer recognised the Yugoslav constitution and laws and started taking over police stations in Serb majority areas.
As evidence in support of his allegations, Milosevic played a recording of a speech by the then President of Croatia, Franjo Tudjman, delivered in Zagreb's central square in May 1992, in which he said that "there would have been no war had we abandoned our goal of independent Croatia."
The accused also quoted Tudjman as saying in Trogir, southern Croatia, on 5 May 1991 that Croatia should switch over to a wartime economy.
Kostic, in turn, quoted Bosnian President Alija Izetbegovic as saying that "Bosnia cannot win independence without war".
The witness said that the Yugoslav military leadership, despite the fact that it mainly consisted of Croatian and Slovene generals and only two Serbs, "undividedly supported the preservation of Yugoslavia, and added that in mid-1991 the Yugoslav federation was led by Croats -- Prime Minister Ante Markovic, Foreign Minister Budimir Loncar and Mesic as president.
Milosevic challenged the credibility of Mesic's testimony saying that Mesic falsely claimed that since March 1991 Milosevic had tried to prevent him from assuming the duties of Yugoslav president. "Mesic lies about even the most exact and easily verifiable facts," he said.
Prosecutor Geoffrey Nice protested over the "unacceptable comment" on the witness, which Presiding Judge Patrick Robinson accepted.
Court-assigned defence counsel Steven Kay intervened on behalf of the accused, saying that Milosevic had the right to seek evidence from his witnesses to determine the credibility of Mesic's testimony.
Mesic gave testimony here to justify his own political ends. Testimony by Mesic and other politicians served their own interests, Kay said, appealing to the judges to allow his client to use Kostic's testimony to refute that of Mesic.
With the help of the witness Milosevic tried to prove that Washington's position on the disintegration of the Yugoslav federation in 1991 evolved under the influence of the strong Croatian community in the United States, illustrating his allegations with recorded statements of former US secretaries of state James Baker and Lawrence Eagleburger.
Judge Robinson did not allow Milosevic to put questions to the witness about this matter, saying afterwards that he did not allow questions concerning the interests of the United States.
Towards the end of the hearing, Milosevic complained about not receiving the necessary medication, saying: "I want you to stop harassing me by denying me medical treatment."
Judge Robinson would not allow him to go into this matter and said that the Trial Chamber had requested a written brief about it.
Milosevic is charged with crimes against humanity committed in Croatia and in Kosovo and with genocide in Bosnia-Herzegovina. The trial continues on Thursday.