Firms not bluffing when they threaten to shift away from London- mayor

Asked about Goldman Sachs CEO Lloyd Blankfein's tweet that he would spend more time in Frankfurt due to Brexit, Khan told BBC radio: "He's articulating publicly what many CEOs and investors who love working in London have been saying privately, which is that unless they have certainty about what happens after March 29, 2019, they have got to make a plan B."

"He's not bluffing. When I speak to businesses each day, they're not bluffing," Khan said

(Reporting by Alistair Smout, editing by Estelle Shirbon)