Former Serbian president Mr Milan Milutinovic is on his way from Belgrade to The Netherlands to surrender to the UN war crimes tribunal at The Hague.
Mr Milutinovic is a key suspect who was indicted in 1999 along with former Yugoslav president Mr Slobodan Milosevic for allegedly organising the mass expulsion of ethnic Albanians from their homes in Kosovo.
He lost his immunity from prosecution when his term in office expired at the end of last year.
Officials said the 60-year-old was accompanied by Yugoslav Foreign Minister Mr Goran Svilanovic aboard a government charter flight.
"By leaving vountarily, Milutinovic fulfilled his legal obligation, thus giving an example to all other indictees," said a statement released by Yugoslavia's council for cooperation with the tribunal.
Mr Milutinovic is accused of being part of a core of decision makers responsible for a brutal crackdown on ethnic-Albanian civilians during the 1998-99 war in the southern Serbian province of Kosovo.
He has denied responsibility for war crimes, claiming he had no power over the Yugoslav armed forces or the Serbian police during their operations against the Kosovo Liberation Army.
At the height of the conflict in 1999, United Nations estimates put the number of ethnic Albanian refugees at up to 800,000 people out of a total population in the province of some two million.
AFP