Eliza Manningham-Buller, who ran MI5 until 2007, has used a BBC lecture to say she hopes British and US intelligence are examining who to talk to within Al Qaeda, as well as how and what could be discussed.

But she says negotiations are still a way off…

Young Arabs, she said, had no opportunity to choose their own rulers. “For them an external enemy was a unifying way to address some of their frustrations.”They were also united by the plight of Palestinians, a view that the west was exploiting their oil and supporting dictators. “It was wrong to say all terrorists belonged to al-Qaida,” added Manningham-Buller.