The incendiary allegation from Christian Wakeford – who defected from the Conservatives to Labour – came after a senior Tory accused government whips of “blackmail” and said the police should be called in.
But Kwasi Kwarteng said he did not believe the claims of threats and intimidation – and turned on Mr Wakeford, calling him a “turncoat”.
“I don’t know what his motivations were and, as you’ll appreciate, he’s a Labour MP now and, of course, part of his job is to try and discredit the government,” the business secretary said.
But other rebel Tories, considering joining moves to topple the prime minister, have also reported threats, including that damaging stories about them will be planted in newspapers.
The Times reported that some are considering publishing private text messages and a secretly recorded conversation with the chief whip, to back up their claims.
Mr Wakeford is believed to have been threatened that the new school would not be built in his Bury South seat if voted with Labour in favour of free school meals, in October 2020.
“I was threatened that I would not get the school for Radcliffe if I did not vote in one particular way.” he said, on Thursday.
“This is a town that’s not had a high school for the best part of 10 years, and how would you feel when holding back the regeneration of a town for a vote?
“It didn’t sit comfortably and that was when I was really starting to question my place at that time.”
Mr Kwarteng, speaking on Sky News, said the government wanted to “get to the bottom” of the allegations – a day after No 10 said there would be no investigation.
But he added: “I’ve been an MP for 12 years now, and I’ve never heard of the kind of allegations that are being made.
“Blackmail, the idea that somehow money is being withheld from communities that need it on account of the behaviour of the MPs, I’ve never heard of anything like that.
“I find it strange because the whip’s office doesn’t actually have the power over spending in that way.” Mr Kwarteng added: “I don’t think that this is happening.”
The bitter Tory infighting is growing as the party awaits Sue Gray’s report into the partygate scandal, which will determine whether Mr Johnson faces a no-confidence vote.
Government nerves are fraying after an email central to the charge that the prime minister “lied to parliament” over the No 10 party he attended was “found”.
Ms Gray is poised to quiz the senior official who sent the email – warning the prime minister’s aide Martin Reynolds to cancel the “bring your own booze” event – it is believed.
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