Boris Johnson described Health Secretary Matt Hancock as “hopeless” early in the coronavirus pandemic, according to a message published by former aide Dominic Cummings

Mr Cummings, who has blamed Mr Hancock for failings during the Covid response, published a screenshot apparently showing a WhatsApp exchange between himself and the Prime Minister.

On March 3 last year, the controversial former aide highlighted the US’s ramping up of testing capacity and criticised Mr Hancock for saying he was “sceptical” about meeting a target.

The Prime Minister purportedly responded: “Totally f****** hopeless.”

Mr Cummings, who left Downing Street in November during a bitter power struggle in No 10, has targeted much of his criticism since leaving at the Health Secretary.

In a blog post exceeding 7,000 words, Mr Cummings also published another private message about the struggles to procure ventilators for Covid-19 patients.

“It’s Hancock. He has been hopeless,” a contact appearing to be Mr Johnson replied on March 27 last year.

In another message, on April 27 last year, the Prime Minister appeared to call the situation around personal protective equipment (PPE) “a disaster” and alluded to diverting some responsibilities to Cabinet Office Minister Michael Gove.

“I can’t think of anything except taking Hancock off and putting Gove on,” Mr Johnson apparently added.

The messages are Mr Cummings’ first attempt to publish supporting evidence since his select committee appearance where he accused the Health Secretary of lying, failing on care homes and “criminal, disgraceful behaviour” on testing.

Mr Hancock has denied the Brexit campaigner’s allegations and said last week it was “telling” that he was yet to provide the joint Health and Social Care Committee and Science and Technology Committee with written evidence.