British intelligence agency MI5 has claimed that it warned the U.K. government of an imminent Al-Qaeda attack on “Western interests” in the weeks leading up to the 9/11 atrocity.

The last warning was given on the morning of the attack itself, though the intelligence did not point to any specific target either in America or elsewhere.

The claim is contained in an official history of MI5, The Defence of the Realm; extracts from which have been published in British newspapers. Its author, Cambridge historian Christopher Andrew, was given access to all MI5 files since the agency was established in 1909.

In a memo dated July 6, 2001— two months before the 9/11 attacks — MI5 warned that there was sufficient evidence to “conclude that UBL [Usama bin Laden] and those that share his agenda are currently well advanced in operational planning for a number of major attacks on Western interests”.

Prof. Andrews writes: “Similar Security Service warnings to Whitehall of imminent attacks continued at intervals...up to including the morning of 11 September.”

Yet, on the day of the attack, Sir Stephen Lander, the then director-general of MI5, reportedly told Tony Blair, Britain’s Prime Minister at the time, that Al-Qaeda was not a “coherent unified terrorist structure”.

Sir Stephen admitted in remarks to The Daily Telegraph that MI5 had been “slow to get going” as it was preoccupied with the IRA activities in Northern Ireland.

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