
Mr Karzai's main challenger, Abdullah Abdullah (r), has repeatedly alleged 'massive, state-crafted' fraud
The government-backed Independent Election Commission in Afghanistan has said that a run-off vote must take place in the presidential election.
President Hamid Karzai, who has come under international pressure, said he accepted the decision and that it strengthened the path towards democracy.
Mr Karzai's main election rival, Abdullah Abdullah, also agreed to the run-off.
The commission said the vote should take place on 7 November.
It agreed with a United Nations-backed panel, the Election Complaints Commission, which found that the cancellation of fraudulent votes had taken Mr Karzai below the percentage required for an outright victory in August's poll.
Newshour's Claire Bolderson spoke to BBC's Martin Patience in Kabul.
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First broadcast 20 October 2009
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