Radovan Karadzic was arrested after more than a decade in hiding
The Hague tribunal has rejected the argument by former Bosnian Serb leader Radovan Karadzic that he should not be prosecuted because of an immunity deal.
Mr Karadzic said the former US peace envoy Richard Holbrooke had promised him immunity from prosecution if he gave up politics.
Mr Holbrooke has repeatedly denied there was any such deal.
The UN court said even if there was, it did not have legal standing, and that Mr Karadzic's trial should go ahead.
Mr Karadzic, 64, faces 11 charges including genocide.
He says Mr Holbrooke, then the US envoy to Bosnia, agreed to provide him with immunity at a meeting with his representatives in Belgrade on 18-19 July, 1996.
Mr Holbrooke - now the US envoy to Pakistan and Afghanistan - has described the claim as "laughable" and "a lie".
The court said on Wednesday that even if such a deal was struck, it would be irrelevant because Mr Holbrooke was not acting with the authority of the UN Security Council.
Mr Karadzic was arrested and brought to the tribunal last year, after more than a decade in hiding.
He is accused of genocide over the massacre of up to 8,000 Bosniaks (Bosnian Muslims) at Srebrenica in 1995, and is also charged with war crimes and crimes against humanity.
The court filed a not guilty plea on his behalf after he refused to offer a plea, saying the court lacked jurisdiction.