The Afghan Independent Election Commission Monday announced the presidential run-off election has been canceled with sitting President Hamid Karzai winning the election.

The decision came after Karzai's top challenger Abdullah Abdullah Sunday withdrew from the run-off set on Nov. 7.

IEC Chief Azizullah Ludin told a press conference in Kabul: " Unfortunately, one of the two candidates Abdullah Abdullah announced his withdrawal from the race on Sunday with only one candidate left, so the IEC, in line with constitution, has canceled the runoff."

"In order to avoid wasting fund, to avoid possible untoward incidents and to avoid creating more confusion about the election, the IEC in line with the constitution has decided to announce Hamid Karzai, the leading candidate in the first-round election, as the president of the country and prays for his success," he said.

Abdullah put forward some conditions one week ago to ensure the credibility of the run-off, including replacing top election official and suspending three ministers. However, the conditions were refused by Karzai.

The first-round election was held on Aug. 20, with preliminary results by Afghan election authority showing Karzai won 54.6 percent. However, a UN investigation on fraud pushed Karzai's total to below the 50 percent, which is needed to avoid a run-off.

U.S. President Barack Obama is weighing his strategy on Afghanistan and considering whether to send tens of thousands additional troops to the war-torn country while Taliban has vowed to disrupt the run-off election.