Pakistan's parliament condemned on Saturday the US raid that killed Osama bin Laden, warning Pakistan might cut supply lines to US forces in Afghanistan if there were further military incursions.
According to one legislator, Pakistan's intelligence chief told a closed session of MPs he was ready to resign over the bin Laden affair, which has embarrassed the country and led to accusations Pakistani security agents knew where the al Qaeda chief was hiding.
There has been criticism of the government and military, partly because bin Laden had apparently remained undetected in Pakistan for years, but also because of the failure to detect or stop the US operation to get him.
"Parliament ... condemned the unilateral action in Abbottabad which constitutes a violation of Pakistan's sovereignty," it said in a resolution issued after security chiefs briefed legislators.
The covert raid by US special forces on bin Laden's house in the garrison town of Abbottabad, 50 km (30 miles) north of Islamabad, has strained already prickly ties with the United States and prompted revenge attacks by his supporters.
On Saturday, a bomb ripped through a bus in Khairian, a small garrison town in central Pakistan, killing at least five people and wounding more than a dozen, police said.
The attack came a day after two suicide bombers attacked a military academy in a northwestern town killing 80 people in what Pakistani Taliban militants said was their first act of revenge for bin Laden's death on May 2.
Pakistan has dismissed as absurd any suggestion that authorities knew bin Laden was holed up in a high-walled compound near the country's top military academy.
The US administration has not accused Pakistan of complicity in hiding bin Laden but has said he must have had some sort of support network, which it wants to uncover.
US Senator John Kerry said that the United States wanted Pakistan to be a "real" ally in combating militants but serious questions remained in their relations.
"But we're not trying to find a way to break the relationship apart, we're trying to find a way to build it," said Kerry, a Democrat close to the Obama administration and who is chairman of the Senate Foreign Relations Committee, told reporters in Afghanistan.
Kerry is due to visit Pakistan in the coming days.
Members of the two houses of parliament said the government should review ties with the United States to safeguard Pakistan's national interests and they also called for an end to US attacks on militants with its pilotless drone aircraft.
They also called for an independent commission to investigate the bin Laden case.
Pakistan officially objects to the drone attacks, but US officials have long said they are carried out under an agreement between the countries.
The legislators said US "unilateral actions" such as the Abbottabad raid and drone strikes were unacceptable, and the government should consider cutting vital US lines of supply for its forces in Afghanistan unless they stopped.
Earlier, a US drone fired missiles at a vehicle in North Waziristan on the Afghan border killing five militants.
It was the fourth drone attack since bin Laden was killed.
Police in Charsadda said that they had recovered for analysis body parts of the two suicide bombers who killed at least 80 struck at a paramilitary force academy.
A Taliban spokesman said on Friday that the attack was in revenge for bin Laden's death and vowed there would be more.
The killing of bin Laden could trigger a backlash from his supporters across a giant area surrounding Afghanistan, the Shangahi Cooperation Council (SCO) regional security body said.
Dominated by China and Russia, the SCO also unites the mostly Muslim ex-Soviet Central Asian states of Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan.
"Craving for revenge, the supporters of al Qaeda, the Taliban movement and other terrorist and extremist organisations may cause a new wave of terror," Kazakh foreign minister Yerzgan Kazykhanov told a meeting with his SCO counterparts in Almaty.
Pakistani intelligence chief Lieutenant-General Ahmad Shuja Pasha, head of the military's main Inter-Services Intelligence (ISI) agency, told parliament in a closed-door briefing he was "ready to resign" over the bin Laden affair, a legislator said.
Pasha, who was asked tough questions by some members of parliament, told the assembly he did not want to "hang around" if parliament deemed him responsible, legislator Riaz Fatyana told reporters.
"I am ready to resign," Fatyana quoted the ISI chief as saying.
Opposition leader and former prime minister Nawaz Sharif said civilian leaders, not the security agencies, should be deciding policy towards India, the United States and Afghanistan.
"The elected government should formulate foreign policy. A parallel policy or parallel government should not be allowed to work," Sharif told a news conference.