A Cabinet minister has said an investigation should be carried out into “completely unacceptable” allegations of Tory critics of Boris Johnson being blackmailed into supporting him.

Business Secretary Kwasi Kwarteng said ministers “need to get to the bottom of the matter” but that he believes it is “very unlikely” the claims made by colleagues are true.

Senior Tory MP William Wragg said critics considering triggering a no confidence vote in the Prime Minister were receiving threats to “withdraw investments” from constituencies, as well as “intimidation” from No 10 staff.

Boris Johnson
Prime Minister Boris Johnson is continuing to fight claims Tory critics are facing ‘intimidation’ which could amount to blackmail (Stefan Rousseau/PA)

Mr Wragg, the chair of the Commons Public Administration and Constitutional Affairs Committee, said the threats could amount to “blackmail” and urged colleagues to report them to the police.

Christian Wakeford, the Bury South MP who defected from the Tories to Labour, then said he was threatened with funding for a new school in his constituency being withheld if he did not vote with the Government over free school meals.

Mr Kwarteng told Sky News: “As far as the specific allegation about whips withholding funds, I think that’s completely unacceptable. Any form of blackmail and intimidation of that kind simply has no place in British politics.

“We need to get to the bottom of the matter. But I find it very unlikely that these allegations are true.”

William Wragg
Conservative MP William Wragg (Parliament TV/PA)

The Business Secretary said Mr Wakeford’s “very serious” allegation has so far been “unsubstantiated”.

“I’m sure it will be investigated if it’s not being so already – after 12 years as an MP I’ve never heard anything like this,” Mr Kwarteng told BBC Radio 4’s Today programme.

“Having been an MP for 12 years I’ve never heard of anyone making a threat, certainly not to me or to anybody else of that kind, doesn’t mean it’s not true.”

But he also described Mr Wakeford, who was elected to Bury South in 2019 on a wafer-thin majority, of having “essentially turned coat” in switching to Labour.

“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,” he told Sky News.

Mr Kwarteng said he had never experienced bullying from the Government whips.

“Generally, my whips were a lot shorter than I was over the years,” he told LBC, adding that therefore “I’m not sure how the physical intimidation or other forms of intimidation” would have been effective.

The damaging claims came as Mr Johnson battled to remain in power ahead of the result of senior civil servant Sue Gray’s inquiry into allegations of rule-breaking partying during coronavirus restrictions.

Sir Keir Starmer and Christian Wakeford
Labour leader Sir Keir Starmer with Bury South MP Christian Wakeford, who has defected from the Conservatives to Labour (Stefan Rousseau/PA)

The result of her investigation is not expected until next week.

On Thursday, the Prime Minister said Mr Wragg’s allegation will “of course” be looked into but insisted he has “seen no evidence” to support it.

But the Times reported that Tory MPs wanting to oust the Prime Minister are considering publishing a secretly recorded conversation with the chief whip and messages to help support the claims.

Mr Wragg is one of a handful of Tory backbenchers to have said publicly they have submitted a letter to the chairman of the backbench 1922 Committee, Sir Graham Brady, calling for a no-confidence vote in Mr Johnson’s leadership.

Mr Wakeford said he had done the same before he defected to Labour shortly before Prime Minister’s Questions this week.

On Thursday, he told BBC North West: “I was threatened that I would not get the school for Radcliffe if I did not vote in one particular way. This is a town that’s not had a high school for the best part of 10 years.”