Some 60 politicians and business leaders have joined forces to urge Theresa May to prepare for a no deal Brexit.
A letter spearheaded by the Economists for Free Trade group said only by making plans to crash out on World Trade Organisation rules can the UK have “real leverage” in the negotiations.
But the demand came at the same time as a warning from five powerful business lobby groups that “time is running out” to secure a deal and save thousands of jobs.
Meanwhile, around 100,000 people marched in central London yesterday, calling for a second referendum on the final Brexit deal.
The Government has set aside cash to prepare for a no deal Brexit – but Leave campaigners are worried ministers could sell them out with compromises to Brussels in desperation to secure an agreement.
In their letter, the 60 ex-Cabinet ministers, economists and business bosses insisted to Mrs May that Brexit could not be stopped no matter how the EU approaches the talks.
“We believe you could… make clear that your preferred outcome is a free trade deal between Britain and the EU, an arrangement that is to the mutual benefit of both parties,” the letter says.
But it argues that “in light of the reluctance of the EU swiftly to secure a free trade deal” the focus must turn to a WTO agreement.
The letter was signed by ex-chancellor Nigel Lawson and Wetherspoon chairman Tim Martin, among others.
But a letter from the Confederation of British Industry, the British Chambers of Commerce, the Federation of Small Businesses and other allies warns that firms will quit Britain if the talks on a deal do not speed up.
Their warning comes after Airbus and BMW warned they could relocate due to the uncertainty surrounding Brexit.
The letter was also singed by manufacturing group the EEF and the Institute of Directors, according to the Times.
According to reports, Foreign Secretary Boris Johnson earlier this month dismissed concerns from bosses at a private event by saying: “F*** business.”
A source close to Mr Johnson told PoliticsHome: “No one has done more to back hardworking British businesses than Boris.
“He was misheard and was actually attacking lobbyists like the EU funded CBI who are more interested in doing what’s right for big multinational corporations instead of helping ordinary working Brits.”
The Department for Exiting the European Union said: “We have made significant progress on our withdrawal agreement and we are now engaged in positive negotiations on our future.
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