Mr Milosevic's prosecutors have said they will present testimony from high-ranking military, diplomatic and political officials who cannot yet be named.

But prosecutors did promise that "many people who have inside information" were ready to assist the Tribunal in order to "make their mark in the record of humanity".

For the prosecution

Witnesses kept secret until they take the stand 90 Kosovo Albanians and 'many people' with inside information May testify - Rade Markovic and Milan Milutinovic Refused to testify - Vlajko Stojiljkovic and Nikola Sainovic

There is intense speculation in the former Yugoslavia about who such people might be - and Mr Milosevic's former associates have been queuing up either to deny they will testify against him or to say they will, if asked.

But all the witnesses who will take the stand have reportedly been sworn to silence and their identities will only become known as the trial progresses.

The refusniks are led by former interior minister Vlajko Stojiljkovic and the former deputy premier Nikola Sainovic - both of whom face the same charges as Mr Milosevic but remain at large.

It is not known whether the jailed former secret service chief Rade Markovic will talk, or Serbian President Milan Milutinovic, who many believe to have cut a deal with The Hague to avoid his own war crimes indictment there.

The prosecution is also hoping to call about 90 witnesses from Kosovo who are expected to paint a graphic picture of the 1998-99 ethnic cleansing operation there allegedly masterminded by Mr Milosevic.

First witness

The first witness called by the prosecutors on Tuesday was a Kosovo Albanian politician, Mahmut Bakalli, once a leading Communist party official who played a role in discussions aimed at ending the political tension that erupted between Albanians and Serbs in the late 1990s.

Bakalli (left) was involved in efforts to avert Kosovo crisis

Mr Bakalli answered questions from the prosecution about the erosion of Albanian rights, such as the banning of the Albanian language in schools.

Mr Milosevic cross-examined the witness aggressively for four hours - often barking out "Yes or no?" at the end of questions - analysing Mr Bakalli's links with the Kosovo Liberation Army and his views on KLA "terrorism".

Mr Bakalli said he had only had political and diplomatic contact with the KLA, but he had urged them to attend the Rambouillet peace talks in France in 1999.

Milosevic wish-list

Mr Milosevic will have to be content with such exchanges with prosecution witnesses for the time being, as it is likely to be months before he can bring his own witnesses to court.

These could include some from a long list of international leaders and politicians whom Mr Milosevic has told the court he wishes to call.

For the defence?

Ex-US President Bill Clinton Ex-US Secretary of State Madeline Albright French President Jacques Chirac UK Prime Minister Tony Blair German Chancellor Gerhard Schroeder Ex-Chancellor Helmut Kohl UN Secretary General Kofi Annan Anyone involved in Dayton accords or Paris agreement

He is determined to accuse them of being behind the 1999 "Nato aggression" against the Serbs - his term for the Kosovo campaign - and to extract an acknowledgement that he was instrumental in ending earlier Balkans conflicts.

But there are a number of hurdles before Mr Clinton, Ms Albright and others, are called to The Hague.

First a list of witnesses must be presented to the court. If the court approves the names - and judges may decide some are not relevant to the charges - it is up to the defence (and Mr Milosevic is defending himself) to persuade them to appear.

But the court does have the power to summon witnesses it deems relevant with a subpoena, and the court could go to the UN Security Council if any country failed to co-operate with the court.

If anyone on the Milosevic wish-list does appear, they needn't expect to be handled with kid gloves about their conduct during Nato's Kosovo campaign.

"When Chirac comes here," Mr Milosevic said during his opening statement, "- and as you know, I have the right to ask for that - I will have to ask him why he did not veto the killing of so many civilians, women, children".