Boris Johnson will realise a no-deal Brexit would be "suicidal" and backtrack on his pledge to deliver it, according to businessman Charlie Mullins.
The Pimlico Plumbers founder, who plans to run as London Mayor, claimed the newly-elected Prime Minister will "put the country first" and seek to delay the Article 50 process.
"If we did leave for some crazy reason we would be heading straight for a recession," he told talkRADIO's James Whale.
"It would be suicidal to leave with no deal and I think we will find Boris Johnson will do a U-turn."
He continued: "He will put the country first, he will realise how damaging it will be and I am certain he will get an extension in October and renegotiate. Even bring in a second referendum."
Mr Johnson has previously pledged to deliver Brexit - deal or no deal - on October 31.
He refused to rule out suspending Parliament in order to get a no deal exit through the House of Commons, which has caused a stir among MPs.
But Mr Mullins insisted there was "no way we're leaving" the European Union without a deal.
"He has got his feet under the table and now is the time to get real, get an extension and start renegotiating."
He added: "There is no better person for it."