Both the United States and Pakistan are affected by the "scourge of extremism" and the U.S. will continue its assistance to the South Asian state, U.S. State Department spokesman Mark Toner said on Tuesday.

"We're both affected by the scourge of extremism. The vast majority of al-Qaeda and bin Laden's victims were Muslim," Toner told reporters at the department, noting that "Pakistan has suffered grievous losses from al-Qaeda attacks."

Calling U.S. assistance "paid dividends," he said the U.S. "will continue to pay dividends."

"This is assistance that is in both Pakistan's long-term interests as well as the United States' national interests and security interests," he added.

Questions were raised about the fitness and legitimacy of Pakistani counterterrorism efforts due to the close proximity of Osama bin Laden's hideout to Pakistan's top army staff college on the outskirts of Islamabad. Some in the U.S. are calling for a halt of aid to Pakistan, which stands at about 20 billion U.S. dollars in direct aid and military payments approved by Congress since 2001.

Before bin Laden was killed on Sunday in his Pakistani hideout in a U.S. military operation, U.S.-Pakistani ties had been frayed over continuing U.S. drone attacks on militants on Pakistan's border with Afghanistan and Pakistan's six-week imprisonment of a CIA contractor for his killing of two Pakistanis.

"We may not see eye to eye on how to approach every issue, but we're going to continue to work with Pakistan, and we believe it's in the best interests of our nation to do so," Toner said.

Writing in the Washington Post on Tuesday, Pakistani President Asif Ali Zardari noted that although his country did not join the U.S. operation on Sunday, "a decade of cooperation and partnership between the United States and Pakistan led up to the elimination of Osama bin Laden as a continuing threat to the civilized world."

He rejected as "baseless speculation" U.S. press reports alleging that Pakistan lacked vitality in its pursuit of terrorism, "or worse yet that we were disingenuous and actually protected the terrorists we claimed to be pursuing."