Former Yugoslav President Zoran Lilic has refused to give evidence against his successor, Slobodan Milosevic.

Mr Lilic was taken against his will from Belgrade to Mr Milosevic's war crimes trial in The Hague, after being seized last week.

But he told the court on Monday he would not testify unless he received guarantees from the Yugoslav authorities that he would not himself be prosecuted for revealing state secrets.

I could be accused of revealing state secrets and that is severely punishable

Zoran Lilic

The Yugoslav Government agreed last week that Mr Lilic should have immunity, but he argued in court that only the president and military chiefs had the power to take the decision.

Mr Milosevic is on trial for alleged genocide and other war crimes in Bosnia, Croatia and Kosovo.

Mr Lilic was Yugoslav president from 1993 to 1997, when Mr Milosevic took over.

Before his arrest, Mr Lilic had made clear that he would not testify against anyone at The Hague.

Milosevic took over the presidency from Lilic

As president of Yugoslavia Mr Lilic should have been senior to the then president of Serbia, Mr Milosevic, but in reality he was little more than a figurehead, taking his his instructions from Mr Milosevic.

The immunity granted to Mr Lilic last week also extends to other close associates of Mr Milosevic, including former state security chief Rade Markovic, who was himself brought to The Hague on Friday.

But Mr Lilic insisted in court that the promise of immunity was invalid.

"Anyone in Yugoslavia can file a complaint against me. I could be accused of revealing state secrets and that is severely punishable," he said.

Hearing delayed

"I am ready to testify before this tribunal should a relevant authority, which means the president, lifts the ban on keeping military secrets.

"I would not like my move to be understood as a contempt of court, but as an attempt to protect myself from any prosecution (in Yugoslavia)," Mr Lilic added.

Mr Milosevic tried to speak, but was silenced by presiding trial judge Richard May.

The hearing was postponed until Friday while the trial judges consider his statement.