Ambassador Susan Rice on "Fox News Sunday" rejected media reports Karzai had lost confidence in the ability of the United States and NATO to defeat the Taliban and could try to cut his own deal with the insurgents.
"Our understanding and what we hear every day is that President Karzai remains committed to his partnership with the United States and NATO," said Rice.
The ambassador said Karzai shared the U.S. view that the Taliban and al-Qaida needed to be defeated in Afghanistan and neighboring Pakistan.
Rice also downplayed the slow pace of U.S. military operations in Afghanistan and allegations Karzai has been dragging his feet in his role. She said the offensive in Kandahar had been slowed down to give commanders more time to shore up the support of civilians living in the region.