Afghan presidential candidate Abdullah Abdullah quit an election run-off today after accusing the government of not meeting his demands for a fair vote, but said he was not calling for a boycott.

Pressure had been growing on Abdullah to withdraw from the contest against President Hamid Karzai, seen by analysts as favourite to win the run-off after getting the most votes in the fraud-marred first round on August 20. "I will not take part in the election ... I have not taken this decision easily," Abdullah told supporters in Kabul.

Karzai's campaign team said the November 7 run-off would go ahead despite Abdullah's withdrawal. Afghanistan has been racked by weeks of political uncertainty, with security also a major concern after a resurgent Taliban vowed to disrupt the presidential run-off.With Afghanistan's political future hanging in the balance, US President Barack Obama is also weighing up whether to send up to 40,000 more troops to Afghanistan. Obama met his top military leaders on Friday as part of a strategic review.

A spokesperson for the White House could not immediately be reached for comment on Abdullah's decision. Abdullah said he quit because the demands he had sought from the government and the Independent Election Commission (IEC), including the sacking of Afghanistan's top election official in the wake of the tainted first round, had not been met.

His voice faltering, Abdullah told tribal elders and supporters gathered in a huge tent in the west of the capital he had made his decision "in the interests of the nation". Later asked by reporters if he would urge his supporters to boycott the vote, Abdullah said: "I have not made that call."

No talks with Karzai at moment
Abdullah's campaign director, Abdulsattar Murad, said talks with Karzai were not on the table at the moment and that Abdullah, the incumbent president's former foreign minister, would likely hold a news conference later today. Abdullah's running mate, Homayoun Assefy, said talks with Karzai could happen after the proposed run-off. "Our campaign is finished," Assefy told Reuters.

"We are not participating. Now it is up to the IEC and we don't have any trust in the IEC." Western diplomats had suggested it was no longer a question of whether he would pull out but the manner in which he did it.

"Abdullah has realised how painful a second round will be for the country. The issue for Abdullah now is how does he withdraw: by saving face gracefully or boycotting the run-off," one Western official in Kabul, who asked not to be identified, told Reuters.

Analysts and diplomats believe withdrawing from the contest, perhaps as part of a power-sharing deal in return for a top government post in Karzai's next government, would spare the country further political pain and insurgent violence. But Karzai's campaign team said it would go ahead with the vote anyway. The run-off was triggered when a UN-led investigation found widespread fraud, mainly in favour of Karzai, had been committed during the first round. - Reuters