The genocide trial of Ratko Mladic was has been broken off after the Bosnian Serb general was taken to hospital for medical checks, a court spokeswoman has said.

"He [Mladic] complained he was feeling unwell during the hearing, so the hearing was adjourned," Nerma Jelacic, spokeswoman for the war crimes tribunal for the former Yugoslavia, told the Reuters news agency on Thursday.

Mladic, 70, was already in poor health when he was arrested in Serbia last year after 16 years on the run. Prosecutors and relatives of victims fear that he could die without facing justice, as happened with former Yugoslav strongman Slobodan Milosevic, who died before he could be sentenced.

Mladic is accused of genocide for his role in the siege of the Bosnian capital Sarajevo and for orchestrating the 1995 Srebrenica massacre of 8,000 Muslim men and boys, Europe's worst massacre since World War Two.

He has said on several occasions that he is too ill to stand trial, complaining that he suffers from the effects of a stroke, has problems with his teeth and has been admitted to hospital with pneumonia.

The court said the hearing would resume on Friday if Mladic is able to attend.