A former chief of Pakistan's intelligence agency ISI has alleged that the United States was behind the October 1999 coup staged by General Pervez Musharraf to overthrow the Nawaz Sharif government.

Commenting on President Musharraf's book In the Line of Fire, former ISI chief Hamid Gul said Musharraf has not stated in his memoirs that Washington was behind his military coup of October 12, 1999.

'It is absolutely true that America played a role in Gen Musharraf's take over of 1999', Gul has been quoted as saying by Daily Times.

Gul also said that successive governments should stop using ISI for political purposes.

He said that he had asked former prime minister Benazir Bhutto to eliminate the political role of ISI when she formed a commission for intelligence reforms, but she rejected his proposal.

Gul also said that Pakistan could defend itself with a nuclear bomb, 'spirit of jihad' and democracy.

"Pakistan is weak and vulnerable without democracy," he said, adding military interventions have always been harmful for the country. "Building a nation was the job of politicians only, but the military could also play a positive role from behind the curtain."