The announcement by U.S. President Barack Obama that American troops will begin pulling out of Afghanistan in July 2011 has raised Taliban morale, according to the country's president, Hamid Karzai.

He also said there would be no progress in the nine-year campaign while insurgents still had safe havens in Pakistan.

His comments have intensified the debate about whether the July 2011 milestone, at which time Canadian troops will also withdraw, was feasible or had encouraged rebels to believe they could hold on until foreign troops started leaving.

Karzai told visiting U.S. congressmen that the date had boosted Taliban morale "to some extent."

"The lack of progress in the war on terror has two factors: one, the terror sanctuaries have not been addressed and second, because civilians were killed," he said.

Washington has emphasized that the deadline will only mark the start of a withdrawal and depends on progress in stabilizing the country.

Karzai has repeatedly voiced frustration that NATO is not doing enough to pursue Taliban sanctuaries in Pakistan. Rangin Dadfar Spanta, Afghanistan's security adviser, said U.S. efforts in Afghanistan were being betrayed by Islamabad's support for terrorists.

"The terrorists' main mentor continues to receive billions of dollars in aid and assistance. How is this fundamental contradiction justified?" he said.