Key email proving Boris Johnson’s top aide was ‘warned’ to cancel No 10 party ‘found by inquiry’

An email central to the charge that Boris Johnson “lied to parliament” over the No10 garden party he attended has been found by the inquiry, it is believed.

Sue Gray is also poised to quiz the senior official who sent the email – warning the prime minister’s aide Martin Reynolds to scrap the “bring your own booze” event – the official has said.

He will tell the partygate inquiry head that Mr Reynolds “immediately came to his office after receipt of the email and asked him why the party should be cancelled”, ITV News has reported.

It is also being alleged that Mr Reynolds, Mr Johnson’s principal private secretary, feared cancelling the May 2020 party would be more embarrassing than going ahead.

The decision to plough on now threatens the prime minister’s job, because of his claim – to the Commons – that no-one warned him it was party that broke Covid laws.

Many MPs believe Mr Johnson cannot survive in office if it is shown that he misled parliament with his repeated denials that parties took place with his knowledge.

Dominic Cummings first alleged that warnings were given – including by himself, to Mr Johnson’s face – arguing it blew apart the prime minister’s defence that he thought the gathering was “a work event”.

Robert Peston, ITV’s political editor, says he knows the identity of the sender of the email, but has agreed not to name him.

The official has said Ms Gray will interview him – and that he will tell her “Reynolds immediately came to his office and asked him why the party should be cancelled”.

Now Mr Peston has added: “I understand Sue Gray has found the email from a senior official to PM’s principle private secretary Martin Reynolds warning him the 20 May party should not go ahead.”

The denial that Mr Johnson was alerted to the party is central to his much-ridiculed Commons apology – when he claimed he believed the gathering was “a work event”.

In a blogpost, Mr Cummings claimed Mr Reynolds also told him he would “check with the PM if he’s happy for it to go ahead”, on 20 May 2020.

“I am sure he did check with the PM. (I think it very likely another senior official spoke to the PM about it but I am not sure),” the post stated.

And it added: “The idea that the PPS [principal private secretary] would be challenged by two of the most senior people in the building, say he’d check with the PM then not – is not credible.”

Earlier, a senior Conservative MP accused ministers of breaching the ministerial code by making threats to rebel colleagues who are considering trying to topple Mr Johnson.

William Wragg urged the MPs to go the police, saying: “The reports of which I’m aware would seem to constitute blackmail.”