BORIS Johnson wanted to stop an inquiry into the source of leaks to the media from Downing Street to protect one of his fiancee’s best friends, Dominic Cummings has alleged.

The former chief special adviser attacked Johnson on his website following accusations from No10 that he had been responsible for handing the media private texts sent from billionaire Brexiteer James Dyson to the Prime Minister.

However, the Prime Minister has denied that Cummings's claims are true. 

It was widely reported that Johnson believed his former right-hand man was trying to “undermine” his government by leaking information to the media.

A source told several right-wing papers that Cummings was “engaged in systematic leaking” after messages showed that Dyson had asked Johnson for a tax issue to be "fixed".

However, Cummings has vehemently denied that he is the source of the leaks. He says he is in possession of private texts exchanged between Johnson and Dyson, but that they relate to “ventilators, bureaucracy and Covid policy - not tax issues”.

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In an explosive post published today, Cummings goes on to accuse the Prime Minister of wanting to halt an inquiry into the source of leaks about lockdown decisions for fear it may implicate one of Carrie Symonds’s friends.

The National:

Symonds (above), the Tory leader’s fiancee, would reportedly have been upset if Johnson had fired Henry Newman, a senior adviser who was at one time tipped to lead the beleaguered Union Unit.

Writing about the goings on in Downing Street after news of an upcoming Covid lockdown was leaked to the media, Cummings claims: “The Cabinet Secretary told the PM that the leak was neither me nor the then Director of Communications and that ‘all the evidence definitely leads to Henry Newman and others in that office, I’m just trying to get the communications data to prove it’.

“The PM was very upset about this. He said to me afterwards, ‘If Newman is confirmed as the leaker then I will have to fire him, and this will cause me very serious problems with Carrie as they’re best friends … [pause] perhaps we could get the Cabinet Secretary to stop the leak inquiry?’”

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Cummings says he told Johnson that attempting to stop the inquiry would be “mad and totally unethical”.

He goes on: “He had ordered the inquiry himself and authorised the Cabinet Secretary to use more invasive methods than are usually applied to leak inquiries because of the seriousness of the leak.

“I told him that he could not possibly cancel an inquiry about a leak that affected millions of people, just because it might implicate his girlfriend’s friends.

“I refused to try to persuade the Cabinet Secretary to stop the inquiry and instead I encouraged the Cabinet Secretary to conduct the inquiry without any concern for political ramifications. I told the Cabinet Secretary that I would support him regardless of where the inquiry led.

“I warned some officials that the PM was thinking about cancelling the inquiry. They would give evidence to this effect under oath to any inquiry. I also have WhatsApp messages with very senior officials about this matter which are definitive.”

The former top advisor says that Johnson knows he is not the source of the leaks and called for an “urgent Parliamentary inquiry into the government’s conduct over the Covid crisis which ought to take evidence from all key players under oath and have access to documents”.

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Cummings also hit out at Boris Johnson over renovations to a Downing Street flat where the Prime Minister lives with Symonds.

He writes: “The PM stopped speaking to me about this matter in 2020 as I told him I thought his plans to have donors secretly pay for the renovation were unethical, foolish, possibly illegal and almost certainly broke the rules on proper disclosure of political donations if conducted in the way he intended.

“I refused to help him organise these payments. My knowledge about them is therefore limited. I would be happy to tell the Cabinet Secretary or Electoral Commission what I know concerning this matter.”

Boris Johnson has denied Cummings's claims are accurate. Asked if it was true that he had wanted to stop an inquiry to protect his fiancee's friend he said: "No, of course not". 

Johnson said he was “mystified” as to why some people have “chosen to attack” his communications team, but declined to say why No10 insiders suspected Cummings was behind the leaks.