A photo of Bin Laden by the Navy Seals

Al Qaeda leader Osama Bin Laden had a staggering £20.8 million when he was killed – that he wanted to be used on waging jihad.

The figure was revealed in a handwritten will that was part of the treasure trove seized by US soldiers after the raid on his compound in Abbotabad, Pakistan, in 2011.

Released for the first time among a batch of 100 documents found inside the building, the will showed that Bin Laden planned to divide his fortune among his relatives, but wanted most of it spent on carrying out the work of the Islamic extremist terror network behind the September 11 2001 attacks.

He urged his family to spend his inheritance on “jihad, for the sake of Allah” – but it is not clear whether any of the inheritance found its way to his heirs.

Other writings from the 9/11 mastermind show that the threat of sudden death was on his mind years before the fatal raid in Pakistan.

In a 2008 letter to his father, he wrote: ”If I am to be killed, pray for me a lot and give continuous charities in my name, as I will be in great need for support to reach the permanent home.”

The documents were released by the US Office of the Director of National Intelligence and show fractures between al Qaeda and al Qaeda in Iraq – which eventually splintered off into what is now known as the Islamic State.

In another letter, addressed to “The Islamic Community in General,” Bin Laden mocked the progress of the war against terror.

He wrote: “Here we are in the tenth year of the war, and America and its allies are still chasing a mirage, lost at sea without a beach.

“They thought that the war would be easy and that they would accomplish their objectives in a few days or a few weeks, and they did not prepare for it financially, and there is no popular support that would enable it to carry on a war for a decade or more.”

He added in the letter, thought to have been written in 2010: “America appears to be hanging on by a thin thread.

“We need to be patient a bit longer. With patience, there is victory.”

More documents found in the compound are set to to be made public next year.