I could be President of the United States, Boris Johnson tells David Letterman

Mr Johnson was in jovial mood as he returned to New York, the city of his birth, to face questions from veteran talk show host David Letterman.

He was quizzed on a host of topics including the 'Boris bike' cycle hire scheme, a similar version of which is soon to be impemented in the US city by New York counterpart Michael Bloomberg, and how long he had been cutting his own hair.

Letterman also put to Mr Johnson, who was in New York to promote London and his new book 'Johnson's Life of London', whether he harboured any desire to become prime minister after his Mayoral term comes to an end.

"I've as much chance of being reincarnated as an olive," the Mayor replied.

When pushed again on his ambitions, Mr Johnson conceded that he could run again for office. Referring to his birth on US soil, he said: "I could be president of the United States, technically speaking."