Pakistan on Friday rejected a US probe into American air strikes that killed 24 Pakistani soldiers, providing little sign of a swift resolution to the worst crisis in the countries' fragile alliance.

"Pakistan's army does not agree with the findings of the US/NATO inquiry as being reported in the media. The inquiry report is short on facts," the military said in a short statement.

"A detailed response will be given as and when the formal report is received," it said.

The inquiry, headed by a US Air Force general, blamed US and Pakistani forces for a series of mistakes that led to "tragic" air strikes on November 26, the deadliest single cross-border attack of the 10-year war in Afghanistan.

The Americans acknowledged for the first time significant responsibility for the strikes, but insisted their troops responded only after coming under heavy machine-gun and mortar fire, angering Islamabad, which has denied any such thing.

The probe portrayed a disastrous spate of errors and botched communication in which both sides failed to tell the other about their operational plans or location of troops, exposing deep distrust.

Pakistan refused to take part in the inquiry, having criticised previous investigations into cross-border attacks as worthless. Instead, it has sought a formal apology from US President Barack Obama.

Islamabad has kept its Afghan border closed to NATO convoys since November 26, boycotted the Bonn conference on Afghanistan and ordered Americans to leave an air base understood to have been a hub for CIA drone strikes on the Taliban.

The 28-day border closure is unprecedented in the 10-year US-led war in Afghanistan, shutting down the quickest and cheapest supply line for 140,000 foreign troops fighting the Taliban.

Analysts in Pakistan saw little in the report that would repair relations, particularly with the government and military in a standoff over alleged attempts by one of the president's aides to rein in the power of the military.

"Our military and government have promoted anti-Americanism on this issue, thereby restricting their own options to re-open negotiations with the US," Lahore-based security analyst Hasan Askari told AFP.

"We are not sure how long they will continue with this stalemate. Given the present crises in Pakistan, neither the civil government nor the military will make a positive move towards the US," he added.

Brigadier General Stephen Clark, who led the probe, said US aircraft carried out three strikes after American and Afghan commandos raiding a village near the border came under heavy machine-gun and mortar fire.

The US did not tell the Pakistanis in advance about the night raid and the Pakistanis had never notified NATO of new border posts in the area, he said.

"For the loss of life -- and for the lack of proper coordination between US and Pakistani forces that contributed to those losses -- we express our deepest regret," the US statement said, stopping short of an apology.

The report upheld much of Pakistan's version of events, namely that the Americans called in the wrong coordinates when asking for clearance to attack, but contradicted Pakistan by insisting its troops came under fire first.

The Pentagon acknowledged the Americans relayed "incorrect mapping information" to the Pakistanis, giving the wrong location for Pakistani troops at border outposts, and found "inadequate coordination" between both sides.

NATO agreed with the findings and said "a series of mistakes were made on both sides in failing to properly coordinate their locations and actions both before the operation and during the resulting engagement".

The episode reflected "an over-arching lack of trust," Clark said.

NATO officers view Pakistan as reluctant to disclose all their border posts and the military in Afghanistan has the impression that when they have shared details, some operations have been compromised, he said.

The air strikes were the latest in a series of crises this year that have brought the fragile Pakistani-US alliance to an all-time low.

In January, a CIA contractor shot dead two Pakistanis and was taken into custody, accused of double murder. On May 2, a covert American raid killed Osama bin Laden near the capital without Washington informing the government.