Washington: On their mission to capture or kill al-Qaeda chief Osama bin Laden, Navy SEAl commandos were authorized by US President Barack Obama to handle Pakistani police or forces if confronted while carrying out the operation.

Obama insisted on incresing forces if confronted during the mission, The New York Times reported.

Pakistan has already said it had scrambled its forces and jets to tackle the foreign forces at Abbottabad, but the US Special Forces left the compound after carrying out the operation in about 40 minutes.

"As the Abbottabad episode illustrates our Military responded to the US Forces covert incursion. The Air Force was ordered to scramble. Ground units arrived at the scene quickly. Our response demonstrates that our armed forces reacted, as was expected of them," Pakistan Prime Minister Yousuf Raza Gilani told Parliament on Monday.

The newspaper said Obama's decision to increase the size of the force sent into Pakistan shows that he was willing to risk a military confrontation with a close partner in order to capture or kill Osama bin Laden.

"Such a fight would have set off an even larger breach with the Pakistanis than has taken place since officials in Islamabad learned that helicopters with members of a Navy Seals team on board had flown undetected into one of their cities, and burst into a compound where bin Laden was hiding," it said.

"Their instructions were to avoid any confrontation if at all possible. But if they had to return fire to get out, they were authorized to do it," a senior Obama Administration official was quoted as saying.

While two helicopters were sent to Abbottabad, according to the original plan, two assault helicopters were going to stay on the Afghanistan side of the border waiting for a call if they were needed.

But the aircraft would have been about 90 minutes away from the bin Laden compound, it said.

"Some people may have assumed we could talk our way out of a jam, but given our difficult relationship with Pakistan right now, the President did not want to leave anything to chance," a senior administration official was quoted as saying.

If a confrontation appeared imminent, there were contingency plans for senior American officials, including Admiral Mike Mullen, Chairman of the Joint Chiefs of Staff, to call their Pakistani counterparts to prevent an armed clash.

But when he reviewed the plans about 10 days before the raid, President Barack Obama raised concern that this was not enough to protect the troops on the mission, administration officials said, according to the newspaper.

That resulted in the decision to send two more helicopters carrying additional troops.

With tensions between the US and Pakistan escalating since the raid, American officials on Monday sought to tamp down the divisions and pointed to some encouraging developments, the paper said.