A former senior aide to Boris Johnson has said she felt like his “nanny” in an unflattering description of his behaviour in the top job, recalling how she scheduled his naps and soothed his “temper tantrums”.

Cleo Watson, brought into No 10 as an ally of Dominic Cummings, described how Mr Johnson needed “house-training” to take precautionary measures to protect others when pinged during the pandemic, how he made jokes such as “kung-flu”, and that he would feign bending over when she went to take his temperature.

The special adviser in No 10 also compared the Prime Minister’s “reluctance” to leave office after a number of ministers quit the Government to Donald Trump, saying Mr Johnson has “never exactly been the commitment type, except in this case, his reluctance to leave did seem a bit ‘let’s storm the Capitol, chaps’”.

She also admits there were days when people at the heart of Government “thought the virus had won, that we had acted too late and that our measures weren’t working”.

He’d kneel on the seats, his elbows propped over the top, like a great unruly golden retriever, howling for attention

The revelations are included in an article Ms Watson has written for Tatler where she describes working as deputy chief of staff and her experience in No 10 ahead of a new Sky drama This England telling the story of the Government’s Covid response.

It includes her version of being let go by Mr Johnson after Mr Cumming’s departure, where Ms Watson says the Prime Minister compared her to an “ugly old lamp” one partner is left with after a divorce.

“He presumably knows better than most how it feels when a marriage breaks up,” she says, one of many barbs aimed at Mr Johnson’s character in a long list of unflattering descriptions of his conduct.

“My role at No 10 sounds fancy, but a lot of the time I was much closer to being Boris’s nanny,” she says, going on to describe regularly taking Mr Johnson’s temperature in the early days of the pandemic, adding: “Each time, never willing to miss a good slapstick opportunity, he dutifully feigned bending over.”

Comparing working in Downing Street to a nursery, she said: “This, plus the constant questioning about whether or not he’d washed his hands (‘What do you mean by ‘recently’?’), the hand-wringing about his hair, which made him look even more like one of those troll toys from the ’80s at the daily televised press conferences, and the frequent scolding about making gags such as ‘Kung-Flu’ and ‘Aye! Corona!’, characterised much of the pre-terrifying brush-with-death era in the nursery.

“During his recovery, the nannying came on in leaps and bounds: my insisting that he drink vitamin-filled green juices from Daylesford instead of his usual Diet Coke; trying to find diary time for his naps or very gradual exercise… I alternated between stern finger-wagging and soothing words in response to his regular ‘I hate Covid now.

“I want everything to go back to normal.

“Why does everything happen to meeeeeee?’ temper tantrums.”

She added: “The PM himself was subject to a fair amount of house-training.

“Like many, he was ‘pinged’ a couple of times and insisted on working from his downstairs office while isolating.

“Very soon, this required setting up chairs as barriers in the doorway, as he couldn’t resist stepping over the threshold into our adjoining room to peer over shoulders at what people were working on (invariably in a pair of someone else’s reading glasses he’d found lying around).

“So the prime ministerial ‘puppy gate’ was created.

“He’d kneel on the seats, his elbows propped over the top, like a great unruly golden retriever, howling for attention.”

Describing the potential for seeing comedy in the situation now that enough time has passed, she said: “Because among the gruelling 18-hour days, horrible days when we thought the virus had won, that we had acted too late and that our measures weren’t working, there was some light relief.”

Downing Street said it did not wish to comment on Ms Watson’s account of her time there.