ISLAMABAD -- The top U.S. military officer pressed Pakistan to rout militants on the border with Afghanistan, saying Tuesday that the government in Islamabad knows what the United States is demanding. Still, it is a pitch Pakistani military leaders have rejected before.

Adm. Mike Mullen's discussion with Pakistan's powerful Army chief and others comes two days before Washington releases an assessment of the war that is expected to say Pakistan sometimes turns a blind eye to militant sanctuaries.

"Clearly the sanctuaries are a priority in our relationship and our discussion," Mullen told reporters traveling with him. "All of us are aware of the impact that it has had in Afghanistan."

President Barack Obama's war strategy depends on squeezing the Taliban-led insurgency on both sides of the rugged border, and the planned annual review will point to safe havens in Pakistan's North Waziristan area as a weak link, U.S. officials have told The Associated Press.

The officials spoke on condition of anonymity because the report is not yet public.

"We all have a sense of urgency about this. We're losing people," Mullen told reporters aboard his plane from Iraq.

He said both countries were falling into the familiar pattern of impatience with one another. What is needed to repair and sustain the fragile relationship is "strategic patience," he said.

Mullen singled out North Waziristan as a gap on Tuesday, as he has before. He also gave Pakistan's answer: There are other priorities for Pakistan more pressing than a military confrontation in a remote and politically sensitive place.

Pakistan will not allow U.S. forces to operate openly on its soil, although a small contingent helps with training. Any campaign to take on militants in the tribal border areas would have to be done by Pakistani forces already fighting insurgent threats elsewhere and still organized primarily to fight rival India.

The Pakistani government has resisted, saying its military is already stretched thin.

Many analysts suspect, however, that Pakistan doesn't want to cross Taliban militants with whom it has historical ties and who could be useful allies in Afghanistan after foreign troops withdraw.

"They know it's a priority for us," Mullen said. "This is a country that we continue to try to build trust with and have a relationship with and get our interests aligned so we're both clearly headed in the same direction at roughly the same time."

The Pakistani military is one among several Pakistani institutions with deep-seated suspicions about U.S. motives and the duration of the U.S. commitment to the region.

Confidential State Department cables recently released by the secret-sharing site WikiLeaks hit a nerve with embarrassing U.S. evaluations of senior Pakistani leaders. The release compounded damage to the fragile partnership between Washington and Islamabad, already strained by stepped-up U.S. drone missile strikes on alleged terrorist hideouts in Pakistan and from incidents this fall in which U.S. forces briefly crossed the border from Afghanistan.

All pricked Pakistan's acute sense of national sovereignty, and fed popular suspicion that the United States is trying to install forces inside Pakistan.

The U.S. has carried out well more than 100 drone strikes in Pakistan this year, roughly twice the number in 2009. The U.S. refuses publicly to acknowledge the covert CIA attacks, but officials have said privately that they have killed several senior Al Qaeda and Taliban commanders over the years.

Almost all of this year's strikes have occurred in North Waziristan.

Pakistani officials often criticize the U.S. drone strikes, calling them a violation of the country's sovereignty. But the Pakistani government allows the drones to take off from bases within the country and is widely believed to provide intelligence necessary for the attacks.

Pakistan's cooperation does have limits. Pakistan recently refused a U.S. request seeking to expand the areas targeted by the drones because of domestic opposition to the strikes, a senior Pakistani intelligence official said Saturday, speaking on condition of anonymity because he was not authorized to talk to the media.

The official from the Inter-Services Intelligence agency would not specify which new areas the American side hoped to target, but an article in the Washington Post identified one as around Quetta, the capital of the southwestern province of Baluchistan, where Afghan Taliban chief Mullah Mohammad Omar is believed to operate.