Bosnian Serb ex-army chief Ratko Mladic's genocide and war crimes trial resumed Monday with the first prosecution witness expected to shortly take the stand.

"Mr Mladic... we will then proceed," presiding Judge Alphons Orie said as he opened the hearing in The Hague, after Mladic finally sat down from demonstratively unpacking a large briefcase and taking out documents.

Mladic, 70, has been indicted on 11 counts of genocide, war crimes and crimes against humanity for his role in the Balkan country's war.

The trial against the man dubbed the "Butcher of Bosnia" was abruptly suspended on May 17, only a day after it opened in The Hague, because of prosecution irregularities.

Mladic faces charges relating to the massacre in the enclave of Srebrenica in northeastern Bosnia, where almost 8,000 Muslim men and boys were murdered by Bosnian Serb troops under Mladic's command.

He also faces charges for the terrorising of the Bosnian capital Sarajevo during 44 months of shelling and sniping which killed 10,000 people.

Prosecutors also hold him responsible for taking some 200 UN peacekeepers hostage and for allegedly ordering his troops to "cleanse" Bosnian towns, driving out Croats, Muslims and other non-Serb residents.

He was arrested in northeastern Serbia last year after some 16 years on the run and subsequently moved to The Hague for trial by the International Criminal Tribunal for the former Yugoslavia.

Mladic has pleaded not guilty to the charges. If guilty, he could face life in prison.