Valdrin Xhemaj / EPA

Kosovar Albanians celebrate in Pristina after the International Criminal Tribunal for the former Yugoslavia cleared the former Kosovo prime minister Ramush Haradinaj of war crime charges on Nov. 29, 2012.

Koen Van Weel / AP

Former Kosovo Prime Minister Ramush Haradinaj in a courtroom in The Hague on Nov. 29, 2012.

Reuters reports — Ramush Haradinaj, a former guerrilla fighter in Kosovo who served briefly as prime minister, was acquitted of war crimes for a second time on Thursday, clearing the way for his return to mainstream politics but angering Serbia.

The retrial verdict by a United Nations court in The Hague comes on the heels of the acquittal on appeal two weeks ago of top Croatian general Ante Gotovina, fuelling nationalist accusations in Serbia that the court is biased against them.

The verdict, and Haradinaj's return to frontline campaigning, could undermine a new effort by the European Union to encourage Serbia and Kosovo to mend ties almost five years after the former southern Serbian province declared independence with the backing of the West. Read the full story.

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Armend Nimani / AFP - Getty Images

Supporters of Ramush Haradinaj celebrate in Pristina on Nov. 29, 2012 after he was acquitted of murder and torture.