Prime Minister Boris Johnson has been moved to intensive care in hospital after his coronavirus symptoms "worsened", Downing Street has said.
Mr Johnson has asked Foreign Secretary Dominic Raab to deputise "where necessary", a spokesman added.
The prime minister, 55, was admitted to St Thomas' Hospital in London with "persistent symptoms" on Sunday.
The spokesman said he was moved on the advice of his medical team and is receiving "excellent care".
A statement read: "Since Sunday evening, the prime minister has been under the care of doctors at St Thomas' Hospital, in London, after being admitted with persistent symptoms of coronavirus.
Mr Johnson was initially taken to hospital for routine tests after testing positive for coronavirus 10 days ago.
His symptoms included a high temperature and a cough.
Earlier on Monday, he tweeted that he was in "good spirits".
Source BBC