This comes just two hours after he thanked people for staying at home in a bid to curb the virus. “Stay home, protect the NHS and save lives,” he tweeted.
“This is a precautionary step, as the prime minister continues to have persistent symptoms of coronavirus ten days after testing positive for the virus,” Downing Street said.
Johnson, 55, became the most high-profile world leader to contract the virus when he announced he had tested positive test 10 days ago.
On Friday, Johnson said he would continue his self-isolation, following a week of staying at home and working remotely, reported AFP.
He has been working from a flat above his Downing Street office, and had been expected to re-emerge on Friday.
But he said in a video message on Twitter: “In my own case, although I’m feeling better and I have done my seven days of isolation, alas, I still have one of the minor symptoms… a temperature.
“So, in accordance with government advice, I must continue my self-isolation until that symptom itself goes.”
Johnson, who in the video still looked under the weather and was seen wearing a shirt without a tie, on March 23 ordered a three-week countrywide lockdown to cut close-contact transmission of the virus.