The UN war crimes court for the former Yugoslavia has assigned a new lawyer to former Bosnian Serb army chief Ratko Mladic for the next four months, a court document said Friday.

"The Deputy Registrar hereby decides to assign Mr Branko Lukic as counsel to the accused for a period of 120 days... effective as of the date of this decision," said the public document, signed by Deputy Registrar Ken Roberts.

Lukic, who hails from Belgrade, was chosen after the court's registry denied a request by Mladic to have his own lawyer Milos Saljic appointed as lead counsel in his case. Mladic was initially represented by another lawyer on the tribunal's list, Aleksandar Aleksic.

Saljic was not eligible to become Mladic's lead counsel because he spoke neither French nor English, the International Criminal Tribunal for the former Yugoslavia's (ICTY) two working languages.

"Branko Lukic is on the Registrar's list of counsel eligible for assignment to indigent suspects and accused... and has indicated his willingness to represent the accused," Roberts said.

The 69-year-old ex-general earlier this month made a second appearance before the court in The Hague following his arrest and deportation from Serbia in May.

Mladic faces 11 counts of genocide, crimes against humanity and war crimes over his role in the 1992-95 Bosnian war in which 100,000 people died.

At his second appearance, Mladic angrily berated judges for no defence lawyer being present.

Mladic is accused of masterminding the Srebrenica massacre -- Europe's worst mass killing since World War II -- and the 44-month siege of the capital Sarajevo from May 1992 in which 10,000 people died.

His trial could take months to get under way and is likely to last several years.

If convicted he could be sentenced to life in prison.