London Mayor: Brexit deal not possible by March 29th Speaking after London's inaugural business awards, Mayor Sadiq Khan says that he believes a Brexit deal is not possible by the current deadline of 29 March, and that if the UK isn't to crash out of the EU it will have to ask for an extension. Khan also says the Labour Party of which he is a member should have acted more swiftly against anti-Semitism. IMAGES of Mayor Sadiq Khan at the London Business Awards AND SOUNDBITES from Mayor Sadiq Khan