US Secretary of State Hillary Clinton said on Friday there is no evidence that senior people in Pakistan knew that Osama bin Laden lived so close to Islamabad.
But she said that the United States and Pakistan needed to do more to battle Islamist militancy and that bilateral relations had reached a turning point.
Mrs Clinton said any peace deal in Afghanistan would not succeed unless Pakistan was part of the process.
She expressed Washington's "strong commitment" to relations with Pakistan.
The BBC reports she was in Pakistan to repair ties badly damaged by the US raid that killed al-Qaeda chief Osama Bin Laden on 2 May.
Mrs Clinton said that the United States had ''absolutely no evidence that anyone at the highest level of the Pakistani government'' knew where bin Laden was.
She said she would return to Washington ''ever more committed'' to the relationship.
''This was an especially important visit because we have reached a turning point. Osama bin Laden is dead, but al-Qaeda and his syndicate of terror remain a serious threat to us both,'' she said.
It was the first such high-level visit to Pakistan since the killing of bin Laden by US special forces in the city of Abbottabad.
The BBC reports that relations between the United States and Pakistan are particularly volatile at the moment.
Some in Washington believe that Pakistani intelligence works closely with extremist groups. Suspicion is rife that some in Pakistan knew of bin Laden's hiding place all along.