Boris Johnson’s spin chief has resigned and become the second key aide to the prime minister to quit in a matter of hours.

Jack Doyle, Number 10’s director of communications, quit his role and is reported to have told staff that recent weeks in Downing Street had “taken a terrible toll on my family life”.

News of his departure came just hours after another of the prime minister’s top aides, Number 10 policy chief Munira Mirza, quit over Mr Johnson’s use of a discredited claim that Labour leader Sir Keir Starmer personally failed to prosecute Jimmy Savile.

Further pressure was heaped on the prime minister over that row when Chancellor Rishi Sunak, widely touted as a potential successor to Mr Johnson, told reporters: “I wouldn’t have said it.”

A Number 10 spokesperson said: “Jack Doyle has left government. He has made a huge contribution and the prime minister is immensely grateful for the work he has done.”