Still angry over the U.S. raid that killed Osama bin Laden, Pakistani lawmakers demanded an end to American missile strikes against Islamist militants on their soil Saturday, and warned that Pakistan may cut NATO's supply line to Afghanistan if the attacks don't stop.

The nonbinding parliamentary resolution reflects the precarious state of the U.S.-Pakistani alliance, which is vital to the war effort in neighboring Afghanistan. The bin Laden raid has brought to the fore a longstanding dilemma that U.S. strikes that Washington says kill militants often are seen by Pakistanis as a violation of sovereignty with mostly civilian victims, exacerbating an already-high anti-American sentiment.

During a visit to Afghanistan, U.S. Sen. John Kerry, chairman of the powerful Senate Foreign Relations Committee, called on Pakistan to be a better partner in the fight against terrorists.

"We obviously want a Pakistan that is prepared to respect the interests of Afghanistan, and to be a real ally in our efforts to combat terrorism," said Kerry, a Democrat from Massachusetts. "We believe that there are things that can be done better."

The Pakistani measure was passed after a rare, private briefing in Parliament by Pakistan's military leaders, who were humiliated by the May 2 U.S. Navy SEAL raid that killed bin Laden in his compound in Abbottabad, a northwest garrison city. Pakistanis were angry the military allowed it to happen while the U.S. said the proximity to a military academy and the capital, Islamabad, raised suspicion that some security elements had been harboring bin Laden.

Washington also has been unable to get Islamabad to go after militant groups, such as the Haqqani network, who use its soil as hideouts but stage attacks only inside Afghanistan. Analysts say Pakistan may be maintaining ties to some insurgents because it wants leverage in Afghanistan — and a wedge against archrival India — once the U.S. pulls out.

Pakistani officials deny links to militant groups, saying they are too stretched battling insurgents attacking the Pakistani state to go after those fighting in Afghanistan right now.

Underscoring the threat, a roadside bomb hit a passenger bus Saturday near Kharian, a garrison town in eastern Pakistan, killing at least six passengers and wounding 20, senior police official Mian Sultan said. The bus was en route to Kharian from the nearby city of Gujrat.

On Friday, two suicide bombers struck a training center for paramilitary police recruits , killing 87 people in the Shabqadar area of Pakistan's northwest in what the Pakistani Taliban called a revenge attack for the death of bin Laden.

Pakistani military officials insist they did not know bin Laden was living in Abbottabad, and U.S. officials say they have no evidence that the top leadership was involved in hiding the 54-year-old al-Qaida chief.

Still, the U.S. didn't warn Pakistan ahead of the raid, and suspicions linger that some elements in its security establishment were helping to hide the terrorist leader.

That has deepened distrust between the two countries, who have had an uneasy alliance since the Sept. 11, 2001, attacks. Ties have frayed in recent months over the case of Raymond Davis, a CIA contractor who killed two Pakistanis in January, as well as missile strikes that have allegedly killed civilians.

Davis, who claimed the two Pakistanis were trying to rob him, was eventually freed after the victims families agreed to financial compensation, even as the U.S. insisted he had diplomatic immunity from prosecution.

The U.S. and NATO rely heavily — though increasingly less — on land routes in Pakistan to ferry non-lethal material to their troops across the border in Afghanistan. That gives Pakistan some leverage in its dealings with the U.S.

Last fall, after NATO choppers from Afghanistan killed two Pakistani soldiers during a border incursion, Pakistan closed the border to U.S. and NATO supply trucks for nearly two weeks.

The parliamentary resolution called the U.S. raid a violation of Pakistan's sovereignty and said Pakistan would not tolerate future such incursions. It also criticized the drone strikes and said the government should consider preventing U.S. and NATO supply trucks from crossing over to Afghanistan if they continue.

The measure doesn't have the force of law, but is likely to be influential because it enjoys broad support from the ruling party and the opposition. It also reflected the political cost in Pakistan of the partnership with the U.S.

It's difficult to say how much of the anger over missile strikes is real and how much of it is Pakistani officials' way of appealing to a domestic audience that is largely anti-U.S. The government is widely believed to secretly aid in the missile strikes.

Few Pakistani lawmakers would discuss the confidential session, which began Friday and stretched into Saturday morning. The length alone suggested that the generals were questioned vigorously — a rarity in a place where the military operates largely out of civilian control.

Intelligence chief Lt. Gen. Ahmed Shuja Pasha admitted negligence in tracing bin Laden, but also noted that Pakistan had cooperated with the U.S. in helping kill or capture numerous bin Laden allies.

When asked why the CIA was able to track bin Laden, the spy chief said the U.S. agency had managed to acquire more sources in Pakistan than the Pakistani agencies because it paid informants far better, according to a lawmaker who attended the session.

"Where we pay 10,000 rupees ($118), they pay $10,000," one lawmaker described Pasha as saying. The lawmaker described the proceedings on condition of anonymity because the session was supposed to be confidential.

Pasha offered to step down if the political leaders demanded it, but none did, according to the lawmaker. Still, Parliament requested that an independent commission probe the U.S. raid debacle instead of one led by generals.


Associated Press writers Ashraf Khan and Munir Ahmed in Islamabad and Riaz Khan in Peshawar contributed to this report.