Former Bosnian Serb leader Radovan Karadzic has appeared in court for the first time since his trial for genocide started in the Hague.
However, he said he would take no further part unless he had more time to prepare his defence.
Mr Karadzic, who has denied all charges and is acting as his own defence counsel, refused to attend the opening last week of the proceedings before the International Criminal Tribunal for the former Yugoslavia.
He faces 11 war crimes charges, including two of genocide during the 1992-95 Bosnian war.
Mr Karadzic said he needs ten more months to prepare, arguing he has been 'snowed under' by 1.3m pages of documents.
'I don't need a new lawyer. I just need time,' he said, adding that preparing a valid defence would normally take a trial lawyer up to two years.
'I don't want to boycott these proceedings but I cannot take part in something that has been bad from the start,' he said when asked by Presiding Judge O-Gon Kwon if he would continue his boycott.
The three-judge panel adjourned the case and said it would decide later this week on how to proceed.
Prosecution witness testimony planned for tomorrow was cancelled pending the decision.
Prosecutor Hildegard Uertz-Retzlaff said options included appointing a standby counsel who could step in if Mr Karadzic refused to participate, or stripping him of his right to represent himself.
'If necessary, force can be used to secure his presence in the courtroom,' Mr Uertz-Retzlaff said.
Prosecutors said in opening statements that Mr Karadzic orchestrated one of 'humanity's darkest chapters' and is responsible for the killings of more than 7,000 Bosnian Muslim men and boys in the village of Srebrenica in July 1995.
The charges also relate to the 43-month siege of Sarajevo by Bosnian Serb forces that began in 1992.
An estimated 10,000 people were killed in the siege as the former Yugoslavia was torn apart in fighting between Serbs, Croats and Muslims.
Prosecutors say Mr Karadzic was the Bosnian Serb supreme commander pursing a campaign of ethnic cleansing during the war.
He stepped down from power in 1996 and had been in hiding as an alternative healer in Belgrade until his arrest in July 2008.
