Legal advisors to Bosnian Serb wartime leader Radovan Karadzic have gone on strike over unpaid fees, officials said Wednesday as Karadzic looked to appeal a UN court's decision to impose a defence lawyer on him.

While 64-year-old Karadzic insists on representing himself at the International Criminal Tribunal for Yugoslavia (ICTY), the genocide and war crimes suspect has eight legal advisors helping him to prepare his defence.

Court papers filed by Karadzic on Wednesday claim his legal team is owed some 70,000 euros (100,000 dollars) in unpaid bills.

Marko Sladojevic, one of Karadzic's eight advisors, said the team stopped work on Tuesday. - Mr Karadzic has been completely on his own since yesterday - he told AFP.

The whole team suspended work because they have not yet been paid. We cannot continue working for free - he added.

Defendants' legal bills are normally paid for by the court. The ICTY declined to comment.

In the filing, Karadzic claims to need 7,500 hours of paid pre-trial preparation time, of which he has been granted only 4,500.

Karadzic faces 11 counts of genocide, war crimes and crimes against humanity for his role in the 1992-95 Bosnian war in which some 100,000 people were killed and 2.2 million forced to flee their homes.

The Bosnian Serb leader has boycotted his trial since it opened on October 26, demanding more time to prepare his defence.

The tribunal ruled last Thursday that Karadzic should be assigned a lawyer if he continues his boycott when the trial resumes on March 1. It also gave the new lawyer three and a half months to prepare.

In a filing, released through his legal team, Karadzic said - the trial chamber's decision is flawed in several respects - and asked for certification to lodge an appeal.

Karadzic insists he should choose a lawyer from a list provided by the court and claims the tribunal erred in not giving reasons for picking the March 1 date, saying it was "seemingly picked out of thin air".

Arrested on a Belgrade bus in July last year after 13 years on the run, he risks life imprisonment if convicted of crimes that include the massacre of 7,000 Muslims at Srebrenica and the 44-month siege of Sarajevo that killed some 10,000 people.