It was received wisdom that none of Johnson’s former aides now in the private sector were likely to accept the risk of a job back alongside the beleaguered prime minister.

Step forward Guto Harri, a former BBC journalist turned PR professional who helped Rupert Murdoch’s News UK after the phone-hacking scandal and worked alongside Johnson during his first term as London mayor in City Hall.

Harri had been working as a director for Hawthorn Advisors, a communications firm founded by Tory co-chairman Ben Elliot.

With his previous communications director on the way out, Johnson clearly turned to a familiar face in his moment of need as he faced a vacuum at the heart of No 10 after the “partygate” scandal.

Harri, who said he was “proud to join a team of capable, grownup and professional and pragmatic people”, will start immediately in a critical week for Johnson’s premiership.

The choice was on one level predictable, as Johnson has often chosen advisers who were longstanding and trusted, such as Sir Edward Lister, Munira Mirza and Ben Gascoigne.

However, it is surprising in other ways given that Harri was a staunch remainer in the Brexit debate and had previously been critical of Johnson, saying in 2018 that he believed Johnson would be a “hugely divisive” prime minister.

These comments were seized on immediately by Dominic Cummings, Johnson’s former adviser who is trying to bring him down, who tweeted: “Message from No10: ‘So our new boss is a pro-Remain lobbyist who’s said the PM is ‘sexually incontinent’, ‘hugely divisive’, ‘destructive’, ‘dragging the country down’, & picked ‘wrong side’ in referendum’ GREAT.”

But Harri has been by no means uniformly critical of the prime minister. He struck a defensive tone towards Johnson on LBC last month, saying people were losing their “sense of perspective” about the story that Johnson was given a cake while happy birthday was sung in the cabinet room in June 2020. “Are we really so prissy, a piece of cake being brought into a meeting is considered sickening?” he said at the time.

During a previous media appearance, Harri denied that Johnson was either a “party animal” or someone who was easy to tempt to “wine o’clock” drinks after work. He also told BBC Newsnight that a “really grovelling apology” could help Johnson survive the “toxic” situation, but added: “The problem at the moment is that nobody seems to be getting a grip.”

After the news of his appointment, Harri responded to Cummings by highlighting an article he wrote in 2020 predicting the adviser’s demise within the No 10 operation. It described him as a “powerful unelected official cultivating a high profile, disagreeing with the prime minister, undermining the cabinet, picking on special advisers, hiring weirdos who can’t survive a week in public life and providing us all with a detailed running commentary of how wonderful this is all meant to be”.

The article contained a defence of the BBC’s place in national life, which contrasts with Cummings’s critical stance towards the broadcaster and could be interesting in light of the government’s plans to abolish the licence fee.

A native Welsh speaker who often tweets in Welsh, Harri started his career as a journalist and later became chief political correspondent for the BBC. He worked for Johnson in City Hall between 2008 and 2014 before going into private PR working for Rupert Murdoch’s News UK as it sought to recover from the phone-hacking scandal.

He made the news last year after being taken off air by GB News for taking the knee during a discussion about racism towards black footballers.

His return to Johnson’s team has thrust him back into the headlines, but his main job will be to see if it is possible to keep his scandal-hit boss out of them.