So that day we were hosted by the Belgian ambassador. This lunch is strictly off the record - no mobile phones, no messages, no interruptions. The cardinals of Nato were basically in conclave.

So we were interrupted, unusually, first of all by one of the ambassadors getting a message from his chauffeur - getting a message that something had happened. That was then followed by one of my bodyguards coming in with a mobile phone.

On alert

So that was two rules broken... and this was my office to say there were reports of one of the planes hitting the World Trade Center.

And I must say I thought, and so did the others who I told, that it was a little trainer aircraft. A few minutes later another phone call came in to say that a second plane had hit, so at that point the lunch was abandoned and we all climbed into cars and came back and I listened in to the World Service to the unfolding story.

I suddenly became very conscious that apart from watching this as a spectator I was also a participant, because of course we are on a direct flight path to what was then a very busy Brussels airport and these planes were roaring overhead.