Bosnian Serb wartime general Ratko Mladic -- accused of genocide and crimes against humanity -- appeared on March 29 at the UN war crimes tribunal in The Hague, where his defense team requested his trial be delayed.
Mladic has been in detention since his arrest and extradition from Serbia 10 months ago.
His trial was due to start this month but has been postponed until May 14.
Mladic complained on March 29 of health problems.
Among other charges he accused of overseeing the killing of at least 8,000 Muslim men and boys in Srebrenica in July 1995.
He also faces charges over the 43-month siege of Sarajevo, from 1992 to 1995.
He faces a maximum sentence of life in prison if convicted.
Mladic denies any wrongdoing.
Based on reporting by dpa and AP