His refusal prompted the judges to enter an automatic not guilty plea on his behalf.
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'I am not going to enter a plea at all,' Karadzic told judge Iain Bonomy of the International Criminal Tribunal for the former Yugoslavia, in The Hague.
'This tribunal does not have the right to try me.'
Mr Bonomy said that he would enter pleas of not guilty on Karadzic's behalf to each of the 11 counts.
Karadzic was arrested in July last year after 11 years on the run, and faces life in prison for crimes against humanity, murder, deportation, terror and unlawful attacks on civilians, and the taking of hostages, including the 1995 massacre of 8,000 Muslims at Srebrenica.
