In an extraordinary attack for an influential Conservative, Tim Montgomerie accused the prime minister of a letting his chief aide control No 10 – partly blaming it for the “mishandling” of the coronavirus response.
Mr Montgomerie revealed he had been threatened with “retribution” for speaking out against the government, having worked for Mr Johnson until as recently as February.
And he said: “What I worry about is that he [Cummings] is a brilliant figure, but half of his ideas are crazy, and half of his ideas are good.
“He shouldn’t be in a leadership position, he shouldn’t be in a dominant position. And I’m afraid that is what has happened inside Downing Street.”
The founder of the ConservativeHome news website added: “The Vote Leave operation that Dominic Cummings ran during the EU referendum has essentially been transplanted into Downing Street, and there is a lack of diversity in thought and personnel as a result.”
The criticisms are all the more damning because Mr Montgomerie said he still considered the prime minister “a friend”, telling BBC Radio 4: “I still want him to succeed – I don’t want a leadership challenge.”
The criticism echoes the private fears of many Conservative ministers and MPs that Mr Cummings enjoys an unprecedented and dangerous status in No 10.
It comes after the aide’s now-notorious lockdown journey from London to Durham was pinpointed as a key reason to explain the recent collapse in Mr Johnson’s poll ratings.
He stood by his ally, despite widespread anger among Tory MPs and Durham Police’s belief that he did commit an offence on his day trip to Barnard Castle.
Mr Montgomerie described Mr Cummings as an “inspirational figure” who had made an “enormous” contribution in delivering Brexit and last year’s general election triumph.
But he said a weak cabinet – after Tory big beasts were ousted for opposing Mr Johnson – demanded a strong Downing Street team, not one in sway to a single, unpredictable figure.
Cabinet meetings were now short and ideas and proposals were dropped “just by the expression Dom wouldn’t wear this”, Mr Montgomerie warned.
In a separate magazine article, Mr Montgomerie wrote: “It took six years for Margaret Thatcher’s governments to begin to stop listening to alternative voices.
“The same patterns had emerged within six months of Johnson becoming prime minister, and within six weeks of his general election victory last December.
“In her early years, the Iron Lady relished argument and intellectual debate – and those internal jousts strengthened her for the public battles with her true opponents.
“In the starkest of contrasts, the team inside today’s No 10 has often preferred to greet internal dissent with retribution – much of it pre-briefed to favoured journalists.”
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