Pakistan's prime minister, Yousaf Raza Gilani, has ordered the army to investigate how Osama bin Laden managed to hide in the country for up to eight years, and has called on the military leadership to answer questions before parliament.

Addressing criticism from US officials, including President Barack Obama, Gilani told parliament it was "disingenuous" to blame Pakistan or accuse its intelligence services of being "in cahoots" with al-Qaida.

"Allegations of complicity or incompetence are absurd," he said. "We didn't invite Osama bin Laden to Pakistan." He also warned Washington that future unilateral strikes could be met with "full force".

The speech came a day after Obama said Islamabad had questions to answer about Bin Laden's "support network" in the country, including possible help from government officials. Gilani retorted that Bin Laden's sanctuary was a "failure of the world" and defended the role of the military's Inter-Services Intelligence spy agency, which has come under sharp attack at home and abroad.

"The ISI is a national asset and has the full support of the government. We are proud of its considerable contribution to the anti-terror campaign," he said.

The forthright speech was an attempt to rally Pakistan's civilian and military leadership in the face of mounting international criticism following the dramatic raid on the compound at Abbottabad, 35 miles north of the capital, Islamabad, that killed the al-Qaida chief.

The ISI had passed "key leads to the CIA" that ultimately led to Bin Laden and helped capture many senior al-Qaida lieutenants since 2001, including 248 in one operation alone, Gilani said.

He paid lip service to the alliance with America and welcomed a forthcoming visit from the US secretary of state, Hillary Clinton. But he pointedly paid tribute to help from China, "a source of inspiration for the people of Pakistan", he said.

Left unsaid was Pakistan longstanding military and nuclear co-operation with China, which is believed to have boosted Pakistan's nuclear programme in the 1990s.

The investigation into the Bin Laden raid is to be carried out by the army's adjutant general, Lieutenant-General Javed Iqbal, Gilani said. The army leadership will address a closed session of parliament on Friday and answer questions on the issue, he said.

Echoing Obama's words one week ago, Gilani said the death of Bin Laden was "justice done" but added: "We are not naive enough to declare victory."

Afterwards jeering broke out among the opposition benches before Chaudhry Nisar Ali, leader of the opposition in parliament, stood up to speak, saying: "I have not heard a single word that addresses the deep discontent of the Pakistani people."