KABUL, Oct. 3 (Xinhua) -- Dr. Abdullah Abdullah, the main challenger for Afghan sitting president Hamid Karzai, on Saturday questioned the role of UN's top diplomat in the country's recently held presidential election.

    Addressing a news conference, Abdullah said there were "serious questions" about the role of the UN special envoy to Afghanistan Kai Eide in the Afghan presidential election held on Aug. 20.

    Abdullah stressed that a panel with United Nations Assistance Mission in Afghanistan (UNAMA) prepared report on the election and the fraud marred process, but the report has yet to be made public.

    The former Afghan Foreign Minister also hinted at the internal strife with UNAMA and the sacking of Kai Eide's deputy, the U.S. diplomat Peter Galbraith, who has accused his UN's top diplomat in Afghanistan of blocking the release of the details of "very extensive" fraud of the Afghan presidential polls.

    The panel, according to Galbraith, formed before elections to monitor election process and to provide report about the voters turnout as well as transparency of election.

    "What happens to that report, where is that report and we want that report to be made public," Abdullah noted.

    However, a UNAMA's spokesman Nilab Mubariz has rejected the claim and told the private television channel Tolo that "UNAMA is impartial in the election process."

    Preliminary result of the election announced last month shows that Karzai by bagging 54.6 percent of votes secured the first position while Abdullah has won 28 percent.