Pakistan's powerful spy agency most likely sheltered Osama bin Laden and hoped to use the al-Qaeda chief as a bargaining chip with the US to strike a deal on Afghanistan before he was killed in a covert Navy SEALs raid in 2011, an ex-ISI chief has said.

"I cannot say exactly what happened but my assessment ...Was it is quite possible that they (the ISI) did not know but it was more probable that they did. And the idea was that at the right time, his location would be revealed," Lieutenant General (retd) Asad Durrani told Al Jazeera.

Durrani said he doubted the official line given by Inter-Services Intelligence (ISI) that it was unaware of the al-Qaeda leader's whereabouts until his death, implying that Pakistan would only have exchanged knowledge of his location in a quid-pro-quo deal.

"And the right time would have been, when you can get the necessary quid pro quo -- if you have someone like Osama bin Laden, you are not going to simply hand him over to the United States," he said.

Durrani, who served as director general of the ISI from 1990 to 1992, emphasised that he had no specific knowledge of the issue but suggested that Pakistan may have been harbouring bin Laden in the hope of getting a bigger say in the future of neighbouring Afghanistan.

"The quid pro quo to my mind...(was) you get your Osama Bin Laden, provided that, now let's agree, let's agree on how to bring the Afghan problem to an end," Durrani said.

Asked whether Laden's compound in Pakistan's garrison town of Abbottabad was an ISI safe house, Durrani said, "If ISI was doing that, then I would say they were doing a good job. And if they revealed his location, they again probably did what was required to be done."



Officially, the ISI maintains that it did not harbour bin Laden and played no part in the raid in 2011.

However, commentators have questioned how bin Laden could have eluded the intelligence agency in the years leading up to his discovery, given the location of the then al-Qaeda chief's compound in Abbottabad.

The Abbottabad Commission, which was set up by the Pakistani government to investigate the circumstances surrounding the raid, charged the military and the government with "gross incompetence" leading to "collective failures" that enabled bin Laden to reside in Pakistan unnoticed and failed to detect the US mission in May 2011.

"The admission of incompetence was probably done on political reasons...As far as the people of Pakistan were concerned, it was going to be very uncomfortable for them that their government, you know, is in cahoots now with the United States and gets hold of Osama bin Laden," Durrani said, adding that bin Laden "was an admired figure in Pakistan".

According to the US, the raid on bin Laden's compound was deliberately conducted without the knowledge of the Pakistani government or its military.