Afghan President Hamid Karzai accused the international community of trying to rig last year's election. (Ahmad Masood/Reuters)

Afghan President Hamid Karzai called U.S. Secretary of State Hillary Clinton on Friday to clarify his assertion a day earlier that the international community interfered in last year's disputed Afghan election.

Karzai accused the United Nations and the international community Thursday of trying to rig the presidential election to either deny him a second term or tarnish his victory.

The Afghan election commission declared Karzai the winner of the Aug. 20 balloting, but a UN-supported independent complaints commission threw out nearly a third of his votes, forcing him into a runoff with challenger Abdullah Abdullah. Abdullah later pulled out of the runoff saying he believed those results would also be tainted.

During his 25-minute phone call with Clinton, the Afghan president "reaffirmed his commitment" to the partnership between the two countries and "expressed his appreciation for the contributions and sacrifices of the international community," said State Department spokesperson P.J. Crowley.

Clinton told Karzai that they should focus on common aims for stabilizing Afghanistan, according to Crowley.

"They pledged to continue working together in a spirit of partnership," Crowley said.

Karzai's comments, delivered Thursday to employees of the Afghan election commission, came after parliament rejected his bid to expand his control over the country's electoral institutions. The remarks were seen as sharpening the power struggle with an increasingly independent-minded parliament over whether foreigners should help oversee parliamentary elections scheduled for September.

The Afghan president acknowledged Thursday there had been "vast fraud" in the August vote but blamed it on the UN and other foreign organizations.

Earlier Friday, White House press secretary Robert Gibbs called Karzai's words "genuinely troubling."