Arron Banks, one of the biggest financiers behind the Brexit campaign, said Brexit Party leader Nigel Farage might stand down even more candidates to secure Britain's exit from the European Union.
Banks said Brexit was under threat unless Prime Minister Boris Johnson won a majority in the December 12 election.
Farage said on Monday that he would stand down Brexit Party candidates in 317 Conservative seats.
Banks told Reuters that he thought Farage would also stand down in Labour marginal constituencies, to avoid splitting the pro-Brexit vote.
"The only way Brexit is going to get delivered is by a Boris majority," Banks said. "Nigel reminds me of a gambler at a casino that’s been winning all night and it’s time to take the chips off the table and step away. What we are offering the geezer, as you might say, is Brexit."
In a reference to Labour leader Jeremy Corbyn, Banks said: "There are 48 hours to save Brexit and save the country from a Corbyn government. We need to see further moves to stand down candidates in marginal seats they can’t win and go for the 40 or so Labour seats where the [Conservatives] haven’t got a hope.”
Banks added: "Brexit is under threat."
The businessman's comments were an unusual public admonishment of his close political ally, although he praised Farage’s success in forcing Britain’s Conservatives not to rule out a no-deal Brexit.
"Nigel has remade the Conservative party in his own image, the Conservative party is the Brexit party,” Banks said.