Mr Duncan Smith is not impressed with White House interventions suggesting Britain should not leave the EU. America would be “pretty insulted” at the meddling if the roles were reversed, he says. “To be fair to the Americans, it’s none of your business. I wouldn’t presume to tell you what to do with your borders with Mexico so why do you presume to tell us what to do with our borders with the European Union. You would tell us to get lost, and quite right too.