UNMIK spokesman Jeff Biely told reporters on Sunday that Haradinai had been elected by the will of members of the legitimate parliament of Kosovo according to democratic procedure, and that UNMIK would respect the result.
At a special session on Saturday, the Serbian government condemned Haradinai's election as an act of provocation and demanded that UNMIK chief Soren Jessen Petersen annul the vote.
Belgrade has initiated an investigation of Haradinai for his role in war crimes committed against minority Serbs in Kosovo in the late 1990s, and there have been rumours that the Hague-based International Criminal Tribunal for the former Yugoslavia (ICTY) will soon issue an indictment against him.
Haradinai has meanwhile rejected all the allegations and accusations against him.