[bots]

The Foreign Office last night issued new guidance telling anyone near the airport to "move away to a safe location and await further advice".

James Heappey earlier told the BBC: "There is now very, very credible reporting of an imminent attack."

He later told us: "The credibility of the reporting has now reached the stage where we believe that there is a very imminent, highly lethal attack possible within Kabul."

Asked by Sky News whether an attack could occur in the coming few hours, Mr Heappey replied: "Yes."

Stressing the "severe" nature of the threat, he told the BBC that it had created an "extraordinarily challenging situation, both on the ground and as a set of decisions to be taken in Whitehall".