One of the two Afghans on a U.N.-backed commission looking into vote fraud in the August presidential election resigned Monday, citing interference by foreigners. Officials acknowledged that errors and miscommunication have plagued the investigation into alleged cheating in the August ballot.

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

The top U.N. official in Afghanistan has said "widespread fraud" marred the Aug. 20 vote, highlighting the extent to which the poll is undermining the credibility of the Afghan government.

But the U.N.-backed Electoral Complaints Commission is repeatedly held up as the potential savior of the election. Western and Afghan officials have said they trust the panel to root out fraudulent votes and produce a fair outcome.

The panel's rulings on how many votes to throw out will determine whether the vote goes to a runoff between President Hamid Karzai and former Foreign Minister Abdullah Abdullah. Preliminary results show Karzai winning with about 54 percent of the vote, but if enough votes are voided, he could dip below the 50 percent needed to avoid a second round.

In announcing his resignation from the commission, Maulavi Mustafa Barakzai alleged that the three foreigners on the panel — one American, one Canadian and one Dutch national— were "making all decisions on their own" without consultation.

The complaints commission rejected the allegation.

Barakzai "was an integral part of the commission and took part equally in all commissioner meetings," the group said in a statement. It said the resignation "will not distract" it from investigations. There will be no interruption in the group's work, said Nellika Little, a spokeswoman for the commission.

U.N. spokesman Aleem Siddique called the resignation "regrettable" but said the U.N. continues to trust that the group will produce a fair outcome.

"We have full confidence in the ECC as the important work continues," Siddique said, adding that the U.N. "stands by the work that they are doing on behalf of the Afghan people."

Barakzai was appointed by the Afghan Supreme Court. It was not immediately clear if the court will be able to appoint a replacement.

Meanwhile, the head of the commission, Canadian Grant Kippen, said a number of errors of interpretation have slowed or complicated the investigation and partial recount.

The process started a week ago. Officials have finished examining a sampling of suspect ballot boxes, but rulings are likely to take days.

Kippen acknowledged that the commission had misinterpreted the statistical analysis that would be used to decide what percentage of votes to void for each candidate. He told reporters last week that each candidate would lose votes in proportion to the number of fraudulent ballots cast for them in a sampling of suspect boxes.

Instead, each candidate will lose the same percentages of suspect votes, based on the number of fraudulent ballots found in the sample, Kippen said Monday.

He said the actual process has not changed and that it is statistically sound, but that confusion stemmed from miscommunication between statisticians who designed the mathematical procedure and commissioners whose role is to determine whether the individual boxes are fraudulent.

He said the mistake was caught and explained to candidate representatives before the commissioners started on their decisions.

"It hasn't affected the process," he said. "It has probably affected people's perception of the process."

This follows a number of missteps that have delayed the fraud investigations. When the complaints commission first issued its order to Afghan election officials to audit and recount ballots last month, the officials said there were problems in the translation from English to the Afghan language of Dari.

New translations were issued and a system for counting a sample of the nearly 3,400 suspect ballot boxes instituted. But then Afghan election officials said many of the boxes earmarked for investigation did not meet the criteria set down by the commission. Scores of new boxes had to be sent for, further delaying the process.

The actual number of ballot boxes included in the audits and recounts have varied from 2,500 to nearly 3,500 over the past two weeks, with officials finally settling on 3,377 boxes on Monday.

Some of the most recent miscommunications may have been the result of the commission's effort to speed the process. Carlos Valenzuela, who helped design the sampling method, said he only learned that the commissioners had misinterpreted his system after they talked to reporters.

"We actually saw this because of reports in the press," Valenzuela said.

The system appears to penalize all candidates equally, regardless of whose camp committed the fraud. Valenzuela said this type of "simple sample" was the only option that would provide accurate results within a limited time.

The vote and the controversy over its outcome have been a setback to hopes of the Obama administration and its international partners that the election would restore legitimacy to a government plagued by weakness and corruption.

In the latest reported violence, the international coalition said its forces killed several militants Sunday in an exchange of fire with insurgents in southern Zabul province's Qalat district.

The same day in neighboring Kandahar province, Taliban militants attacked a border police outpost and police killed 14 insurgents in the ensuing clash, said Gen. Saifullah Hakim, the border security chief for the southeastern part of the province.