The Hague - Congolese former rebel Bosco Ntaganda has gone on hunger strike and is refusing to appear at his international war crimes trial in protest against his detention conditions, judges were told on Tuesday.

Ntaganda has also instructed his defence team to stop acting on his behalf at his trial which opened at the International Criminal Court in The Hague a year ago.

In a long, rambling, written statement seen by AFP, Ntaganda, who was absent from the courtroom, said "there is no possibility that I will see my wife and children again under normal conditions".

"That's why I am ready to die."

Last week, presiding judge Robert Fremr refused to lift visiting restrictions, citing concern he could be trying to interfere with witnesses or intimidate them.

But Fremr insisted "nothing in the restrictions prevents family visits from taking place".

Ntaganda has denied 18 charges of war crimes and crimes against humanity arising out of savage ethnic attacks carried out in the Democratic Republic of Congo by his rebel Patriotic Forces for the Liberation of Congo (FPLC) in 2002-2003.

Ethically-charged wars

In his statement, read in court by his lawyer he said, "When I gave myself up three years ago, I thought I would be able to defend myself. But I know now that is not the case. I know there is no way out, and I no longer have any hope."

The judges rejected a defence request to adjourn the trial until Monday, and said the hearings would resume on Wednesday, ordering his defence team to appear in court to represent him.

The judges also ordered that a medical professional should assess Ntaganda's fitness and that a visit from his family should be arranged expeditiously.

Prosecution lawyer Nicole Samson argued that the "onset of depression seems to have been a fairly speedy one and appears in our submission ... to be a manipulative tactic aimed at halting proceedings and negotiating with the chamber."

Ntaganda was handed over to the ICC after he turned himself into the US embassy in Kigali in 2013.

The eastern Democratic Republic of Congo has been mired for two decades in ethnically-charged wars, as rebels battle for control of its rich mineral resources.

Prosecutors say the man once dubbed "The Terminator" played a central role in the Ituri conflict which rights groups believe alone has left some 60 000 dead since 1999.