A former Yugoslav spy has been cross-examined by former Yugoslav President Slobodan Milosevic at the UN war crimes tribunal in The Hague.

Slobodan Lazarevic, who said he worked as an under-cover agent during the war in Croatia, has been providing some of the most incriminating testimony the court has heard so far.

But Mr Milosevic has been trying his best to discredit him.

If you are insinuating that somebody gave me a large cheque to appear here, you are quite wrong, Slobodan Lazarevic

The prosecution is aiming to prove that, although he was the President of Serbia, Slobodan Milosevic had considerable influence over the Croatian Serb leadership, their army and police.

Mr Lazarevic said on Tuesday that Mr Milosevic controlled and financed the Bosnian Serb and Croatian Serb armies during the conflict in the early 1990s.

He told the court that Mr Milosevic was known as the "boss" during a campaign to expel non-Serbs from parts of Croatia.

But in his cross-examination, Mr Milosevic suggested he was a nobody with no inside information and had been bribed to give fabricated evidence.

'No large cheque'

Mr Lazarevic, a solid, serious-looking man who served with Serbia's military intelligence in the self-declared Serb republic of Krajina, stood up to the attacks.

The war in Croatia destroyed communities

"If you are insinuating that somebody gave me a large cheque to appear here, you are quite wrong," he said.

The witness said he had seen deliveries of cash and weapons for Croatian Serbs arrive from Belgrade.

"I heard the orders came from Belgrade, and Belgrade is synonymous with you," he said.

Mr Milosevic replied: "That's a very large synonym."

Earlier, Mr Lazarevic explained that he became disillusioned with army intelligence when he was escorted to Serbia with Croatian Serbs who had surrendered to the Croatian army in 1995.

He said, with tears in his eyes, that they were sent to what he described as a concentration camp run by the paramilitary group Arkan's Tigers as punishment for surrendering to the Croatians.

He said they were beaten and otherwise mistreated.

Mr Lazarevic said on Tuesday that Mr Milosevic's government instructed rebel Serbs to block potential peace deals in Switzerland, Austria and Norway in the early 1990s.

He said Belgrade provided the money for Croatian Serb delegations to attend the conferences and instructed them not to agree on anything.