UK businesses have run out of time to prepare for the consequences of Britain leaving the European Union in March without an exit deal, a government audit showed on Wednesday.

The findings by the National Audit Office, the government’s spending watchdog, were published with London and Brussels at loggerheads in Brexit talks.

They threaten to deal a political blow to Prime Minister Theresa May, who has made the phrase that “no deal is better than a bad deal” her mantra.