THE HAGUE - Bosnian Serb wartime leader Radovan Karadzic refused to enter a plea on genocide charges Tuesday at the UN's Yugoslav war crimes court, prompting the judges to enter an automatic not guilty plea on his behalf.

"I am not going to enter a plea at all," Karadzic told judge Iain Bonomy of the International Criminal Tribunal for the former Yugoslavia, in The Hague.

"This tribunal does not have the right to try me."

Bonomy replied: "I shall enter pleas of not guilty on your behalf" to each of the 11 counts.

Judges of the tribunal last week approved the prosecution's third, amended indictment against Karadzic, which lists two genocide charges and nine of war crimes and crimes against humanity.

Karadzic, arrested on a Belgrade bus in July 2008, 13 years after he was first indicted by the ICTY, is charged over his role in Bosnia's 1992-1995 war.

The main allegations against the 63-year-old relate to the 44-month siege of Sarajevo that left 10,000 dead, and the July 1995 massacre of around 8,000 Muslim men and boys in Srebrenica.

Among other things, the prosecution has charged Karadzic with having sought to "permanently remove" Bosnian Muslims and Croats from Serb-claimed territory, and to "eliminate" Bosnian Muslims in Srebrenica.

He also stands accused of spreading terror among the civilian population of Sarajevo through a sniping and shelling campaign from April 1992 to November 1995, and of taking hostage UN personnel to prevent air strikes against Bosnian Serb military targets.

But Karadzic repeated his claim Tuesday that an agreement with former US diplomat Richard Holbrooke had given him immunity from prosecution.

"I am challenging the jurisdiction of this tribunal ... on the basis of my agreement with the international community whose representative at that point in time was Mr Richard Holbrooke."