Prime Minister Boris Johnson has spent the night in intensive care at a central London hospital after his coronavirus symptoms worsened.
Downing Street said he was moved to the unit on the advice of his medical team and was receiving “excellent care”.
Mr Johnson has asked Foreign Secretary Dominic Raab to deputise “where necessary”, a spokesman added.
The prime minister, , was admitted to St Thomas’ Hospital with “persistent symptoms” on Sunday evening.
The Queen has been kept informed about Mr Johnson’s health by No , according to Buckingham Palace.
World leaders – including US President Donald Trump and French President Emmanuel Macron – have expressed their support for Mr Johnson.
BBC political corre spondent Chris Mason said the prime minister was given oxygen late on Monday afternoon, before being taken to intensive care.
He was moved as a precaution so he could be close to a ventilator – which takes over the body’s breathing process
“Over the course of [Monday] afternoon, the condition of the prime minister has worsened and, on the advice of his medical team, he has been moved to the intensive care unit at the hospital. “
It continued: “The PM is receiving excellent care, and thanks all NHS staff for their hard work and dedication.”
Mr Raab – who will later chair the government daily Covid – meeting – said there was an “incredibly strong team spirit” behind the prime minister .
He added that he and his colleagues were making sure they implemented plans Mr Johnson had instructed them to deliver “as soon as poss ible “.
” That’s the way we’ll bring the whole country through the coronavirus challenge, “he said.
Intensive care is where doctors look after the sickest patients – his admission to ICU is the clearest indication of how ill the prime minister is.
We do not know the full details of Mr Johnson’s condition, but he is conscious and not being ventilated.
Not every patient in intensive care is ventilated, but around two-thirds are within hours of admission with Covid – . This is a disease that attacks. the lungs and can cause pneumonia and difficulty breathing.
There is no proven drug treatment for Covid – , although there are many experimental candidates.
But the cornerstone of the prime minister’s care will depend on getting enough oxygen into his body and supporting his other organs while his immune system fights the virus.
Chancellor Rishi Sunak said his thoughts were with the prime minister and his pregnant partner, Carrie Symonds, and that Mr Johnson would “come out of this even stronger”.
On Saturday, Ms Symonds said she had spent a week in bed with the main symptoms. She said she had not been tested for the virus.
Scotland’s First Minister Nicola Sturgeon said she was “sending [Mr Johnson] every good wish”, while Northern Ireland’s First Minister Arlene Foster added she was “praying for a full and speedy recovery”.
Wales’ First Minister Mark Drakeford called it “concerning news “.
Mr Johnson’s predecessor, Theresa May, and former Labor leader Jeremy Corbyn both said their thoughts were with him.
Mrs May noted that the “horrific virus does not discriminate.”
The Taoiseach – Irish Prime Minister – Leo Varadkar wished Mr Johnson “a rapid return to health”, and French President Emmanuel Macron said he hoped he “overcomes this ordeal quickly.”
European Commission President Ursula von der Leyen also wished him a “speedy and full recovery”.
For Archbishop of Canterbury Justin Welby, the news “deepens our compassion for all who are seriously ill” and those looking after them.
And Mayor of London Sadiq Khan tweeted that St Thomas’ Hospital had “some of the finest medical staff in the world” and that the prime minister “couldn’t be in safer hands”.
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During the government daily coronavirus briefing earlier on Monday, Mr Raab stressed that the prime minister had been continuing to run the government from hospital.
Asked whether that was appropriate, Mr Raab said Mr Johnson would “take the medical advice that he gets from his doctor.”
“We have a team … that is full throttle making sure that his directions and his instructions are being implemented,” he said.
The Foreign secretary added that he had not spoken to the prime minister since Saturday.
Health Secretary Matt Hancock, who also tested positive for the virus and spent time in self-isolation, offered “all possible best wishes to Boris Johnson and his loved ones”.
“I know he will receive the best possible care from our amazing NHS, “he tweeted.
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