Former Bosnian Serb leader Radovan Karadzic has requested to interview a U.S. diplomat and be given access to documents he says prove he was offered immunity to war crimes charges at the U.N. Yugoslavia tribunal.

Court documents showed on Monday Karadzic is seeking access to U.S. government documents he says detail promises about his arrest or prosecution made by former U.S. peace envoy Richard Holbrooke during meetings held in July 1996 with the then Yugoslavian President Slobodan Milosevic in Belgrade.

Holbrooke, who forged the Dayton agreement ending the Bosnian war, has repeatedly denied Karadzic's claims of a secret immunity deal since the former Bosnian Serb leader was arrested last July after more than a decade on the run.

Court documents also showed on Monday Karadzic is requesting permission for a legal adviser to interview diplomat Philip Goldberg, who he says was one of the U.S. representatives who accompanied Holbrooke to the alleged Belgrade meetings.

Karadzic, representing himself with the help of legal advisers, is on trial in The Hague for war crimes and genocide charges over the 1992-95 Bosnian war. The charges include the 1995 massacre of 8,000 Muslims at Srebrenica.

He has had a plea of "not guilty" entered for him.

U.S. legal counsellor Denise Manning has said the United States is willing to search for and provide documents and to make Goldberg available for an interview if the court approves Karadzic's request, the court documents showed.

As part of his request, Karadzic has agreed not to disclose any information gained from the United States with its consent.

The Yugoslavia tribunal ordered the prosecutor in December to provide full disclosure of any documents it possessed that might indicate whether undertakings were made at the alleged Belgrade meetings, but stressed any immunity agreement would be invalid under international law.

The prosecution replied in January, saying that it did not possess any such documents.