The top U.N. official in Afghanistan on Sunday acknowledged "widespread fraud" in the disputed presidential election and rejected allegations from a former deputy that he covered up cheating to smooth the path to victory for President Hamid Karzai.

The remarks by Norwegian diplomat Kai Eide appeared designed to win back respect for both the troubled U.N. mission and the entire election process ahead of a ruling by investigators on whether fraud was extensive enough in the Aug. 20 balloting to require a runoff.

Eide's reputation was tarnished when his deputy Peter Galbraith alleged that the U.N. mission chief downplayed allegations of widespread ballot-stuffing by Karzai's supporters. Galbraith, the top-ranking American in the U.N. mission, was fired Sept. 30 by U.N. Secretary-General Ban Ki-moon after the widely publicized dispute.

A U.N.-backed fraud panel is expected to decide this week whether to throw out enough votes to require a runoff between Karzai and his top challenger, Abdullah Abdullah. Doubts about the U.N.'s neutrality could throw the panel's rulings into question.

The Obama administration and its international partners had hoped the vote — the first presidential election run by Afghans — would restore legitimacy to a government plagued by weakness and corruption. Instead, widespread allegations of ballot-box stuffing have sullied Karzai's reputation and Galbraith's accusations threaten to undermine the credibility of the U.N. which helped organize the election.

In a separate news conference, Karzai told reporters that "confusion" over election results had been "created by Western elements in our country." He did not elaborate.

During a press conference, Eide said Galbraith's allegations were untrue in some cases and taken out of context in others. Eide was flanked by ambassadors from the United States, Britain and France in a show of international support for the U.N. mission and its embattled leader.

Eide said he could "only say that there was widespread fraud" and that "any specific figure at this time would be pure speculation" until the recount is complete. Eide said Galbraith's allegations against him have "affected the entire election process."

Final results have been delayed by more than a month as a U.N.-backed panel set up as a check on the Afghan-appointed election commission examines complaints and suspicious votes. Though preliminary tallies show Karzai winning with about 54 percent, enough Karzai ballots are suspect that the voiding of fraudulent votes could drop him below the 50 percent threshold needed to avoid a runoff.

Eide said he remains "committed to the process" and pointed to the ongoing fraud investigations as proof that systems set up to catch cheating are working.

Last week, Galbraith said he was sticking by his allegations. He accused the United Nations of failing to exercise its responsibility to oversee the Afghan elections, adding that "the fraud that took place in Afghanistan was preventable."

Four U.N. staffers who worked under Galbraith have resigned over the dispute, U.N. spokesman Aleem Siddique said.

Among other things, Galbraith complained that polling stations were allowed to open in areas that were insecure, raising the likelihood of fraud. Eide said military operations were launched in a bid to secure to open as many stations as possible.

Eide said that closing such stations would have denied a large number of people the opportunity to vote and created "an important element of potential instability in the country."

Many polling stations believed affected by fraud were in areas of the Taliban-controlled south where turnout was low.

Eide denied that he had told U.N. staffers not to pass on credible information about ballot-stuffing or low-to-nonexistent turnout. However, he said reports from second- or third-hand sources were not reported because they did not appear credible.

"Some of these allegations are based on private conversations whilst he was a guest in my home for two months," Eide said. "My view is that private discussions around the dinner table remain just that: private."

Eide said both he and the U.N. mission have suffered from the accusations, and that the charges have also "heightened the temperature" of discussions about elections, making it harder to convince people that the process will be fair.

Once the election results become clear, President Barack Obama is expected to complete a review of Afghan strategy and decide whether to accept a recommendation by his top commander here, Gen. Stanley McChrystal, for up to 40,000 more troops.

Among the options under review is a plan to maintain U.S. troop numbers at their current levels and shift the focus to missile strikes and special operations against Al Qaeda leaders, including those sheltering in neighboring Pakistan.

In the latest fighting, U.S. and Afghan forces stormed a mountainside compound in eastern Afghanistan before dawn Sunday and killed more than a dozen militants in a compound used by an Al Qaeda figure, according to the U.S. military.