Security fears over Zardari's nuclear arsenal

Pakistan is portrayed in newly released secret cables as an unreliable friend to the United States and Britain, with a civilian leader who worries about being "taken out" by his army and an ingrained ambivalence about co-operating fully on nuclear proliferation and the fight against terror.

The revelations, many drawn from diplomatic messages sent from Islamabad by Anne Patterson, the US ambassador there until October, to the State Department in Washington, are likely further to strain the already extremely complicated relationship between Pakistan and America.

Some of her cables are concerned with alleged foot-dragging by Pakistan to follow through with an agreement reached in 2007 to allow the US to remove for safekeeping a stockpile of highly enriched uranium near one of its nuclear energy plants. The uranium is no longer needed for the plant but could be used for bombs. It remains in Pakistan today.

"Our major concern is not having an Islamic militant steal an entire weapon but rather the chance someone working in the government of Pakistan facilities could gradually smuggle enough material out to eventually make a weapon," Ms Patterson told her superiors in Washington in February 2009.

It was during a conversation with Vice President Joseph Biden that Pakistan's President, Asif Ali Zardari, allegedly alluded to his own political weakness by saying that his military "might take me out".

Mr Biden travelled to the country shortly before his inauguration at the start of 2009 and, in a conversation about pursuing the Taliban and al-Qa'ida, asked Army Chief General Ashfaq Parvez Kayani if he could be sure they "had the same enemy as we move forward". The latter, according to one cable, responded: "We are on the same page in Afghanistan, but there might be different tactics." Thus Mr Biden came home with little clarity.

There is potential embarrassment for Islamabad in parts of the cables that reveal in black and white that even last year, the Pakistan Army had acquiesced to have a small number of US Special Operations soldiers travel with it on patrols in parts of the country's north-west, where the Taliban and groups supporting them have bases.

But it is the issue of the fissile material that is most awkward. The cables show that the concern of the US is shared by Britain. "The UK has deep concerns about the safety and security of Pakistan's nuclear weapons," Mariot Leslie, a senior Foreign Office official, is reported as telling a US counterpart in September last year.

Ambassador Patterson says in one cable that Pakistan was balking on removal of the material for fear the transaction would leak to the media, which would portray it as America trying to rob the country of its nuclear capability. The Pakistani government had concluded that "the 'sensational' international and local media coverage of Pakistan's nuclear weapons made it impossible to proceed at this time".