Almost ten weeks of political paralysis in Afghanistan was brought to a close yesterday when a presidential election run-off was cancelled and President Karzai was declared the winner after the withdrawal of his only rival.

Western leaders, desperate to end a crisis that has undermined their efforts to defeat the Taleban, rushed to endorse the decision by the Independent Election Commission (IEC) and congratulate Mr Karzai.

Abdullah Abdullah, who pulled out of the race on Sunday in protest at the failure of Mr Karzai to tackle electoral fraud, appeared to accept the decision after coming under pressure from the international community.

Questions remained over the legality of the result, which gives Mr Karzai another five-year term in office. The Afghan leader is expected to make a victory speech today and will be inaugurated before world dignitaries this month. His re-election lacks credibility because he did not win the necessary outright majority in the first round on August 20, after which a UN-backed investigation disqualified a million of his votes because of fraud.

Western officials were still trying to broker a power-sharing deal between Mr Karzai and Dr Abdullah to prevent a potentially dangerous split between the Tajik-dominated north and the predominantly Pashtun south.

“The point is, Karzai’s mandate is very, very, tenuous,” Nick Horne, a former UN political officer in Afghanistan who worked on the elections, told The Times.

The IEC, whose top officials were appointed by Mr Karzai, said that it made the decision because of the cost and risk of organising the run-off on Saturday. It added that a one-horse race would compromise the president’s legitimacy.

“The Independent Election Commission declares the esteemed Hamid Karzai as the President . . . because he was the winner of the first round and the only candidate in the second round,” Azizullah Ludin, the IEC chief, told a news conference.

Asked if he was concerned that Mr Karzai did not have a legal mandate, he told reporters: “We are the commission: we have decided.”

Dr Abdullah withdrew in protest at Mr Karzai’s refusal to meet his minimum conditions for a fair run-off, which included dismissing Mr Ludin.

The IEC had insisted on Sunday that the constitution required the run-off to proceed with only one candidate. However, Zekria Barakzai, an IEC spokesman, said yesterday that a one-horse race would have breached an article of the constitution stating that two candidates must contest a run-off. “We are not in Saddam Hussein’s Iraq, we are not a communist state where there is only one candidate,” he said.

Western officials had been pushing for the run-off to be cancelled, fearing low turnout, further fraud and more Taleban attacks. Some suggested that the Supreme Court should make a ruling on the issue but others said that would only prolong the crisis because the court was appointed by Mr Karzai. “There’s no appetite anywhere in the international community for a second round,” one Western official said. “No one wanted the Supreme Court to get involved. It would only have made a messy process even messier.”

Western governments were, therefore, quick to endorse Mr Karzai’s victory, pre-empting any legal challenges. President Obama telephoned Mr Karzai to congratulate him, telling the Afghan leader that the US expected a more serious effort to end corruption in his Government.

“I emphasised that this has to be a point in time in which we begin to write a new chapter,” Mr Obama said.

Gordon Brown also called Mr Karzai. Speaking to the Commons soon after the conversation, the Prime Minister said: “Afghanistan now needs new and urgent measures for tackling corruption, for strengthening local government, for reaching out to all parts of Afghan society and for giving the Afghan people a real stake in their future.

“President Karzai agreed with me that Afghanistan now also needs to strengthen its army and police numbers, so that over time we can reduce the number of British troops.”

A Downing Street spokesman added that Mr Karzai’s inauguration would bring forward plans to increase the number of British troops in Afghanistan by 500 to 9,500.

Mr Karzai’s victory is expected to allow Mr Obama to announce a decision in the next few days on whether to send up to 40,000 more US troops. The US Embassy welcomed the decision by the IEC, which it said was taken “according to its mandate under Afghan law”.

Ban Ki Moon, the UN Secretary General, congratulated Mr Karzai after meeting him and Dr Abdullah earlier in the day. UN and US officials have been trying to broker a deal under which the two rivals would divide ministries and provincial governorships, according to several diplomats. The US Embassy said that Karl Eikenberry, the US Ambassador, was meeting both men regularly.

Diplomats said that the US and its allies would press Mr Karzai to form a Government free of suspected war criminals and drugs traffickers. “In the eyes of the Afghan people and in the eyes of the international community he has to rebuild his credibility,” a Western official said. “If we see thugs, criminals and drug dealers in the Cabinet, international support will wither.”

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