The most ruthlessly ambitious actor in British political life ruled himself out ever becoming prime minister on Friday, insisting he had “no ambition” in that direction.
He then ruled himself back in, saying, “we will see what happens”.
Boris Johnson told reporters at a Politico event Newseum in Washington DC that his current job "gluts the appetite for power".
He suggested it would be some "babe unborn" that would take over the Conservative leadership from David Cameron, adding "it isn't going to be me".
Asked if he had any political aspirations to become prime minister, Johnson replied: "No. My aspirations are to continue to do this job in London and then we will see what happens. I think that by the time the whole - I once said something about the ball coming loose from back of the scrum, or something like that, a rugby metaphor."
He continued: "The ball shows absolutely no sign of coming loose whatever. The ball has been propelled forward by the scrum with David Cameron with the ball at his feet going for the line and there's going to be a huge pushover try. I'm bound in somewhere at the back and that's where I am. It may be that some babe unborn will take over from Prime Minister Cameron, but it isn't going to be me."
Johnson told the invited audience that former US Secretary of State Hillary Clinton, with whom he had talks in New York earlier this week, believed Europe was being "too wimpy" in the way it was dealing with Russian president Vladimir Putin over the crisis in Ukraine - but added that he was paraphrasing the meeting.
He said: "She's extremely compelling on a large number of subjects but one thing in particular she really wanted to get across and that was that she thought that the Europeans were being too wimpy in dealing with Putin. I'm summarising there, she did not use that word."
He added: "She thought in particular that we in Britain should be less dependent on Russian hydro-carbons and she thought we should get on with seeking alternative sources."
Johnson also mocked Bobby Jindal for talking "complete nonsense", after the Republican governor of Louisiana claimed there were "no-go" areas in the British capital in which only Muslims are allowed.
Speaking on Friday morning at an event in Washington D.C hosted by POLITICO, Johnson said could offer the potential presidential contender a "gentle education" on the "jumbled up" ethnic mix in London.
On Thursday, Johnson took a swing at the British politicians, saying that Westminster was going through a "very rocky period", while suggesting financial devolution to the cities would help to "electrify" the British political scene. The slight came ahead of Boris' own bid to return to Westminster in May.