Prime minister Boris Johnson has spent a second night in an intensive care unit at St. Thomas' Hospital in London as he battles to overcome coronavirus.
A statement issued by Number Ten said that Johnson was being kept in intensive care for "close monitoring". He has been in hospital since Sunday after being initially admitted for tests.
Health minister Edward Argar said on Wednesday that the prime minister was "stable" and "in good spirits".
Argar went on to pour cold water on the prospect that the UK Covid-19 lockdown would be reviewed on Monday as was originally hoped, informing the BBC that the scientific evidence "isn't there" to enable the government to make a decision on easing measures thus far.
Argar said: "We have to be over that peak before we can think about making changes. It's too early to say when we will reach that peak."
Speaking at Wednesday's daily coronavirus briefing, foreign secretary Dominic Raab told the public that standard oxygen treatment was being administered to the prime minister without the need for a ventilator or more intense breathing apparatus.
Raab said: "I'm 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 at the helm, leading us through this crisis in short order."
Raab added that he would continue to deputise for Johnson when required, but any major decisions would be made collectively by the cabinet.
"We've got very clear directions, very clear instructions from the prime minister, and we're focused with total unity and total resolve on implementing them so that when he's back, I hope in very short order, we will have made the progress that he would expect and that the country would expect."