A MAJOR Conservative Party donor has delivered a blow to Boris Johnson’s hopes of clinging to power, telling the Prime Minister he’s beyond “the point of no return”.

Finance mogul John Armitage, who has previously handed more than £3 million to the Tories, told the BBC that leaders should quit if they lose “moral authority”.

It comes as Johnson faces a police investigation into allegations of law-breaking parties in Downing Street, several of which he is reported to have attended in person.

The Tory leader is also under fire for spouting baseless claims about Keir Starmer being responsible for the failure to prosecute Jimmy Savile, which has preceded the Labour leader being accosted outside Parliament by an angry mob.

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Armitage told BBC Radio 4 he found the turmoil engulfing Number 10 “tremendously upsetting”.

Asked by Laura Kuenssberg if Johnson was “past the point of no return”, the Tory donor replied: “Well, personally yes.”

He continued: “Politicians should go into politics to do good for their country. That is the overwhelming reason to be in politics. I don’t think it’s about your own personal sense of getting to the top of a snakes-and-ladders game.

“And I feel that, if you lose moral authority, and if you do things which … the average person – your mother, someone you try to explain to, someone who you admire – if you do something or say something, which on the front page of the Sunday Times looks terrible, and you do that consistently, and you betray a sense of not really caring, I think you should leave.

“And I find the lack of honour inherent in modern politics incredibly distressing.”

The National: CALLS: Prime Minister Boris Johnson leaves 10 Downing Street. Photo: Jonathan Brady/PA Wire

Johnson has tried to offset bad news stories this week with a minor shake-up of his ministers, as well as a turnover of No 10 staff – reported to be an attempt to win over backbenchers.

But Armitage was unimpressed. He commented: “It’s about more than like, ‘If I’m failing, I’ve done a few things wrong, oh gosh, I’m going to change my advisers, God above!’

“What about a sense of personal responsibility? You know, ‘I’m going to change my chief of staff and it will all be fine’. Oh, really?”

Armitage has donated more than £500,000 to the Tories since Johnson became Prime Minister, but he has also given money to Labour, including £12,500 in March.

The BBC reports Armitage has told the Conservative Party he will not be giving it any more money as things stand, but he plans to remain a member.

In response to Armitage, a senior Downing Street source insisted that the Prime Minister remains “entirely focused on delivering for the British people”.

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Johnson will face MPs in the Commons on Wednesday after carrying out a limited reshuffle which saw Mark Spencer moved from chief whip to Leader of the Commons, with the previous holder of that role, Jacob Rees-Mogg, becoming Minister for Brexit Opportunities.

New chief whip Chris Heaton-Harris told BBC’s Newsnight: “I would like to think we have a very strong Prime Minister who is going to continue and get stronger and stronger and lead us into the next election, which we will win comfortably.”

Spencer’s continued role in government has raised eyebrows as he continues to be investigated over his role in MP Nusrat Ghani’s allegations of Islamophobia.

Johnson asked the Cabinet Office to “establish the facts” regarding the Tory MP’s claim that she was told by a whip her dismissal as a minister in 2020 was because of concerns about her “Muslimness”. Spencer identified himself as the whip but denied her accusation.

Tory health minister Edward Argar told Times Radio: “There is an investigation going on into those specific allegations that were made … So it wouldn’t be right for me to comment while that process is going on.

“Speaking on the basis of my working relationships, and as a colleague, I’ve always found Mark to be an incredibly decent, forthright and genuine person and I found him to be a highly effective chief whip.”