Vojislav Seselj, leader of Serbia’s extreme nationalist Radical party, received a 15-month prison sentence for exposing protected witnesses during his trial in The Hague for war crimes.

Mr Seselj “intentionally” revealed names and other details about three witnesses in one of his books, published after the United Nations tribunal’s protection order. He admitted he was the author, yet in March pleaded not guilty to the resulting contempt of court charge.

However, the contempt sentence appeared largely theoretical amid doubts by the prosecution about how to move forward with Mr Seselj’s trial for war crimes and crimes against humanity. The 15 months would theoretically be subtracted from his credit for “time served” if he was eventually convicted in his main trial, tribunal experts said.

The Serb Radical leader – accused of sending his followers to murder, rape, torture and deport Muslims, Croats and other non-Serbs in the early 1990s – could receive the maximum sentence of life in prison. But judges suspended hearings in his case in January because of questions about the safety of 10 remaining prosecution witnesses, said Nerma Jelacic, spokesperson at the UN tribunal for the former Yugoslavia.

The tribunal has already held Mr Seselj for more than six years, partly because of his constant disruptions, apparently meant to please party supporters in Serbia. In conducting his own defence, he has chosen the same method as Radovan Karadzic, the former Bosnian Serb leader arrested last year, and Slobodan Milosevic, the former Yugoslav president who died in The Hague in 2006 before a verdict.

Judges ordered Mr Seselj to ensure the offending book’s withdrawal from his Internet site by August 7.

Although he retains loyal followers, the once-feared opposition party that he commands from the UN cell block, often through telephone calls with Belgrade, appears to be slipping to the fringe of the Serbian political scene.

Tomislav Nikolic, the former acting leader on Mr Seselj’s behalf, last year broke ranks to form a more moderate party, which balances Serb nationalism with support for joining the European Union.

Mr Nikolic’s Progressives have this year captured three municipal seats from the Radicals and kept up pressure on Serbia’s ruling Democrats. Earlier this month, the ex-Seselj deputy went to Brussels and met Olli Rehn, EU enlargement commissioner.

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