“I”ve got a Union Jack onesie,” admits Boris: London Mayor reveals he has an all-in-one during Twitter Q&A session

'I've got a Union Jack onesie,' admits Boris: London Mayor reveals he has an all-in-one during Twitter Q&A session | UPDATED: 01:13 GMT, 26 December 2012 Onesie: A patriotic all-in-one outfit similar to the one Boris Johnson has said he owns In his defence, he only wore it the onesie.