Covid 19 coronavirus: British PM Boris Johnson 'improving' after ICU admission

Britain's Prime Minister Boris Johnson has spent two nights in ICU battling coronavirus. Photo / AP

British Prime Minister Boris Johnson's condition is improving and he is now "sitting up in bed" after spending two nights in the intensive care unit.

Johnson tested positive for coronavirus nearly two weeks ago and has spent two nights receiving treatment in St Thomas' Hospital.

Chancellor Rishi Sunak informed the daily Downing Street press conference that the Prime Minister, who is still in intensive care, was receiving "excellent care" at St Thomas' hospital.

"I can also tell you that he has been sitting up in bed and engaging positively with the clinical team," he said.

Britain's Prime Minister Boris Johnson speaks from self isolation after contracting coronavirus. Photo / AP

It comes as England recorded its deadliest day of the pandemic so far on Wednesday, with another 828 deaths pushing Britain's total death toll past 7000.

More than 1,452,000 cases of coronavirus have now been confirmed across 184 countries, and more than 83,000 people have died.

Cabinet Office minister Michael Gove yesterday revealed Johnson wasn't on a ventilator.

"He's not on a ventilator no," Gove told LBC radio. "The Prime Minister has received some oxygen support and he is kept under, of course, close supervision."

Gove admitted Johnson's intensive care battle was "truly frightening" and said ministers were "praying" for his swift recovery.

The 55-year-old was transferred to intensive care at 6am (NZT) Tuesday because of breathing difficulties - forcing him to "deputise" Raab to take the reins of government.

The PM's sharp downturn came 11 days after he first suffered coronavirus symptoms and went into isolation. He looked increasingly unwell when glimpsed in public and in "selfie" videos posted on social media, and ministers were then shocked by his grim appearance at a Zoom conference on Sunday.