One of the two Afghans on a United Nations-backed commission looking into vote fraud in the August presidential election resigned Monday, citing interference by foreigners.

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. Officials acknowledged that errors and miscommunication have plagued the investigation into alleged cheating in the August ballot.

Once the election results become clear, U.S. 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, Gen. Stanley McChrystal, for up to 40,000 more troops.

The top UN 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 UN-backed Electoral Complaints Commission is repeatedly held up as the potential saviour 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 run-off between President Hamid Karzai and former Foreign Minister Abdullah Abdullah.

Preliminary results show Karzai winning with about 54 per cent of the vote, but if enough votes are voided, he could dip below the 50 per cent needed to avoid a second round.