Vojislav Seselj, a Serbian ultra-nationalist, burned EU and NATO flags after an international court ordered him to return to The Hague to face trial for his war crimes in the former Yugoslavia.
Seselj was initially charged in The Hague during the war between Bosnia and Croatia as Yugoslavia fell apart.
He was freed by the United Nations court in November 2014 on compassionate grounds, but after four months, judges in The Hague changed their minds and ordered him to return, saying he had broken the terms.
He rejected the new verdict and told supporters he would never go back to The Hague, which has set March 31 as the date for giving its verdict on his alleged role in fomenting the Balkan wars of the 1990s, when he headed the biggest party in Serbia's parliament and led paramilitaries in wars in Croatia and Bosnia.
"I will not go voluntarily, but I will use every opportunity to inflict expert, professional, political and moral damage on the Hague tribunal," Seselj, 61, told several dozen cheering supporters of his Radical Party in front of the High Court in Belgrade.
He then held up an EU flag and said, “It burns well” to the supporters as he set it alight. A NATO flag also received the same treatment.
Serbia has committed to cooperate with The Hague Criminal Court regarding the extradition of Yugoslav war criminals in return for the opening of its membership bid for the European Union.