Four of Boris Johnson's closest aides out amid Savile controversy and partygate

Director of communications Jack Doyle was confirmed to be leaving the Downing Street operation just hours after head of policy and long-term ally of Mr Johnson Munira Mirza resigned over the “scurrilous” Savile smear.

Mr Doyle was embroiled in allegations of lockdown-breaching parties in Downing Street. Later it emerged Downing Street chief of staff Dan Rosenfield and the Prime Minister’s principal private secretary Martin Reynolds had also resigned, according to reports.

Chancellor and Yorkshire MP Rishi Sunak criticised the Prime Minister for his remarks, telling reporters he “wouldn’t have” made the same comments accusing Sir Keir Starmer of failing to prosecute Savile during his time as Director of Public Prosecutions.

Speaking at a Westminster press conference last night, Mr Sunak praised Ms Mirza as a “valued colleague” and criticised the Prime Minister’s remarks, saying “I wouldn’t have said it”.

Mr Johnson had back-pedalled on the Savile claim, which has been debunked by fact checkers, but the comments were not enough to convince Ms Mirza, who has been with him since London City Hall, to stay.

“I believe it was wrong for you to imply this week that Keir Starmer was personally responsible for allowing Jimmy Savile to escape justice,” a letter seen by The Spectator magazine read.

“There was no fair or reasonable basis for that assertion. This was not the usual cut and thrust of politics; it was an inappropriate and partisan reference to a horrendous case of child sex abuse. You tried to clarify your position today but, despite my urging, you did not apologise for the misleading impression you gave.

“You are a better man than many of your detractors will ever understand which is why it is so desperately sad that you let yourself down by making a scurrilous accusation against the Leader of the Opposition.”

The Prime Minister is continuing to face criticism from his own ranks on the partygate scandal and the way it was handled.

Yesterday morning, Yorkshire grandee David Davis said he would be recommending to his constituency party that he submits a letter, after he called on Mr Johnson to quit in the House of Commons just a fortnight ago.

The Haltemprice and Howden said: “I will recommend that we send in a letter, but I will take their views first.”

He added: “My concern about this, as I said when I intervened two weeks ago, was that this would be a death of a thousands cuts over months or even over a year, which is what’s happened with every previous leader of the Conservative Party who has been removed; it’s taken a long time.”