THE HAGUE, Netherlands - A judge at the Yugoslav war crimes tribunal Wednesday rejected challenges by Radovan Karadzic and said the UN court had jurisdiction to try him on charges of genocide and crimes against humanity.

The decision by judge Iain Bonomy in a 33-page ruling took the case of one of the key figures of the Balkan wars of the 1990s one step closer to trial, which could start later this year.

The former Bosnian Serb leader objected to several parts of his 11-count indictment in motions filed since his arrest July in Belgrade.

Bonomy said none of Karadzic's arguments persuasively challenge the court's jurisdiction.

Prosecutors had no immediate response to the rulings. It was not immediately clear if Karadzic -- who is conducting his own defense -- will appeal Bonomy's decisions.

Among motions rejected by Bonomy were a Karadzic challenge to the two genocide charges against him and to the court's jurisdiction to try him for the taking hostage of UN peacekeepers.

Many of the issues he raised were expected to form part of his defense at trial.

Prosecutors allege Karadzic was part of a criminal conspiracy to create an ethnically pure Serb ministate in Bosnia by killing and expelling Bosnian Muslims and Croats during Bosnia's 1992-95 war.

In one victory for Karadzic, Bonomy ordered prosecutors to draft a change to part of the 38-page indictment charging Karadzic on the basis that he could have predicted certain crimes would be committed.

Karadzic is alleged to have orchestrated the deadly shelling and sniping campaign in the capital Sarajevo and the murder of some 8,000 Muslims following the 1995 fall of the UN-protected Srebrenica enclave.

Bonomy entered not guilty pleas to all charges on Karadzic's behalf after the former Bosnian Serb leader refused to enter pleas.

If convicted, Karadzic faces a maximum sentence of life imprisonment.