Dominic Cummings is self-isolating at home after showing symptoms of coronavirus, Downing Street has confirmed.

The prime minister’s top adviser is understood to have fallen ill over the weekend and remains at home, while staying in contact with the Downing Street team during the quarantine period.

Mr Cummings, a key member of Boris Johnson’s inner circle, was last spotted racing away from Downing Street on Friday after the news broke that the prime minister had tested positive for Covid-19.

The news will raise fresh questions over whether senior government figures have been following social distancing advice after Mr Johnson and Matt Hancock, the health secretary, were both diagnosed with coronavirus.

Dominic Cummings spotted running away from Downing Street shortly after PM tests positive for coronavirus

The chief medical officer, Chris Whitty, and Scottish secretary, Alister Jack, are also self-isolating after displaying symptoms of the virus last week.

Mr Johnson continues to display “mild symptoms” and hopes to be out of isolation by Friday, his spokesperson confirmed.

“We are following the guidelines, which say you should self-isolate for seven days from when you had symptoms,” the prime minister’s official spokesperson told a Westminster briefing.

“He is chairing the daily meetings using video conferencing facilities. He is working from the chancellor’s office. He has been able to do everything he needs to do to lead the coronavirus response.”

On Mr Cummings, the prime minister’s spokesperson said the top aide was self-isolating at home after developing symptoms over the weekend.

Mr Johnson remains in charge of the government’s response, continuing to work from No 11 and holding meetings by video conferencing.

Dominic Raab, the foreign secretary, will deputise for the prime minister if his condition worsens.

Speaking from his No 11 flat on Sunday night, a croaky Mr Johnson praised 20,000 former NHS staff who have returned to the service to tackle the pandemic.

Boris Johnson thanks medical professionals from coronavirus isolation

“We are going to do it, we are going to do it together.