Washington sent Special Forces into Pakistan last summer after intercepting a call by the Pakistani army chief referring to a notorious Taleban leader as a “strategic asset,” a new book has claimed.

The intercept was ordered to confirm suspicions that the Pakistani military were still actively supporting the Taleban whilst taking millions of dollars in US military aid to fight them, according to the “The Inheritance,” by the New York Times correspondent David Sanger.

In a transcript passed to Mike McConnell, the Director of National Intelligence in May 2008, General Ashfaq Kayani, the military chief who replaced Pervez Musharraf, was overheard referring to Maulavi Jalaluddin Haqqani as “a strategic asset”. The remark was the first real evidence of the double game that Washington had long suspected President Musharraf was playing as he continued receiving US military aid while aiding the Taleban.

Mr Haqqani, a veteran of the anti-Soviet mujahidin wars of the nineties, commands a hardline Taleban group based in Waziristan and is credited with introducing suicide bombing into themilitants’ arsenal.

Washington later intercepted calls from Pakistani military units to Mr Haqqani, warning him of an impending military operation d esigned to prove to the US that Islamabad was tackling the militant threat.

“They must have dialled 1-800-HAQQANI” a source told Mr Sanger. “It was something like, ‘Hey, we’re going to hit your place in a few days, so if anyone important is there, you might want to tell them to scram’.”

The intercept was the clue that led the CIA to uncover evidence of collusion between the Pakistani Inter-Services Intelligence agency (ISI) and Mr Haqqani in a plot to carry out a spectacular bombing in Afghanistan. Two weeks later, India’s Embassy in Kabul was bombed, killing fifty-four people and prompting a CIA mission to Islamabad to challenge the government with their evidence.

The first cross-border strike took place in early September without Islamabad’s knowledge after Washington concluded that no one could be trusted with the information.

General Kayani, a former ISI chief, became army chief when Mr Musharraf relinquished that post in 2007, a year before he was forced to quit as president. Worryingly for Washington, General Kayani remains Pakistan’s army chief.

Mr Musharraf reacted angrily to the book’s allegations of double-dealing, which appeared in the Pakistani press for the first time yesterday. “Get your facts correct, I have never double-dealt,” Mr Musharraf told Pakistani television stations.

“There is a big conspiracy being hatched against Pakistan, to weaken the Pakistan army and the ISI to weaken Pakistan.”

Mr Sanger’s book, detailing the foreign policy challenges inherited by the Obama Administration, was published in the US last month. In it, US intelligence officials also speak of their fears that Islamist militants might launch a spectacular attack on Indian soil in the hope of ramping up tensions on the subcontinent, leading Pakistan to deploy its nuclear weapons.

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