A police officer stands in front of barriers erected outside St. Thomas' Hospital in London on Monday. British Prime Minister Boris Johnson was in the hospital on Monday undergoing tests after suffering "persistent" symptoms of coronavirus for 10 days. Photo: AFP

British Prime Minister Boris Johnson was spending a second night in intensive care battling the coronavirus which has infected more than 55,000 people across the country and killed about 6,200.

"He stayed at work for you... now pray at home for him," The Sun tabloid splashed across its front page Wednesday while the Daily Express said: "Boris 'will pull through.'"

Deputizing for Johnson, Foreign Secretary Dominic Raab said he was "confident he'll pull through, because if there's one thing I know about this prime minister, he's a fighter and he'll be back, leading us through this crisis in short order."

In an update Tuesday evening, the prime minister's spokesman said his "condition is stable and he remains in intensive care for close monitoring."

He earlier said the 55-year-old Conservative leader was receiving "standard oxygen treatment and breathing without any other assistance" and had not required a ventilator.

Johnson is the most high-profile government leader to become infected with COVID-19 and messages of support flooded in from across Britain and the world.

He was admitted to intensive care on Monday evening after spending Sunday night in hospital following concerns he still had a cough and high temperature 10 days after being diagnosed with COVID-19.

His transfer to intensive care is unprecedented for a prime minister during a national emergency.

For many people, it brought home the seriousness of the disease that has so far seen 6,159 deaths in Britain, with a record 786 more reported in a daily update on Tuesday.

AFP