Afghanistan's election commission said Thursday that the country's presidential election will be held Aug. 20, when voters around the country will decide whether to keep President Hamid Karzai on the job. The election falls due this year in the spring, according to the Afghan constitution, but Azizullah Loden, the head of the country's Independent Election Commission, said the security situation is not strong enough to hold elections then. Loden said that additional international forces would arrive in the coming months, and that their presence would improve security and allow the vote to be held. U.S. military leaders have said that up to 30,000 new American forces could be sent to Afghanistan in 2009. Thousands of those troops are being sent to the country's south, Afghanistan's most violent region. The delay in the vote -- which effectively will give Karzai several more months in office than the five-year term he was elected to -- is allowed by a clause in the constitution addressing a lack of security for a peaceful vote, Loden said. Other Afghan officials have said the country simply doesn't have enough time to declare candidates, print ballots and distribute them around the country by spring. Distributing ballots in Afghanistan's mountains during winter or early spring would be an impossible task, officials have said. Several Afghan politicians have said they will run against Karzai, but none of the candidates who have declared so far is expected to present Karzai with a strong challenge. Election officials have been holding voter registration drives around the country the last several months. But worries have arisen that Afghans in the country's most violent districts will not be able to take part in the vote.