Former Bosnian Serb army commander Gen. Ratko Mladic has slammed the United Nations' Yugoslav war crimes tribunal as a "satanic court" at the start of his testimony as a defense witness for his former political master, Radovan Karadzic.

In a historic courtroom reunion of the two alleged chief architects of Serb atrocities during Bosnia's 1992-95 war, Mladic was testifying under subpoena Tuesday for Karadzic, the former Bosnian Serb president.

Both men are on trial separately for crimes including genocide. They both insist they are innocent.

Mladic initially refused to testify, telling Presiding Judge O-gon Kwon, "Your subpoenas, your platitudes, your false indictments, I do not care one bit about any of it."

Kwon then briefly adjourned the trial so Mladic's dentures could be retrieved from his cell.