The London major, brim full of London 2012 Olympics enthusiasm, has provided a couple of unintentionally funny moments over the last few days.
The latest sees Johnson exclaim, “Come on whoever you are doing whatever you’re doing, fantastic!”
The mop-headed major was watching today’s women’s double sculls rowing final in which Team GB pair Katherine Grainger and Anna Watkins won gold.
When he realised he was watching the British team, Johnson exclaimed: “She’s going to win!”
When it was explained to Boris by a soldier that the pair were only half way through the race he apologised, saying: “Oh, half way, sorry. Pick it up now, they’re a length ahead now, come on Team GB!”
On Wednesday Johnson was filmed dangling from a zipwire with two Union Jacks in his hands.
Watch Boris Johnson’s Olympic rowing commentary
