Boris Johnson was admitted to St Thomas’ Hospital in London on Sunday after for tests after the Covid-19 symptoms persisted 10 days after testing positive for the virus. He has now been moved to an ICU.

British Prime Minister Boris Johnson, who was diagnosed with the coronavirus more than a week ago, has been moved to the intensive care unit (ICU) of a London hospital after his Covid-19 symptoms worsened on Monday. Boris Johnson was admitted to St Thomas’ Hospital in London on Sunday after for tests after the Covid-19 symptoms persisted, 10 days after testing positive for the virus.

Boris Johnson’s office released a statement after the British prime minister was moved to the ICU. In the statement, Boris Johnson’s office said, “Over the course of this 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.”

Downing St said Boris Johnson was conscious and does not require ventilation at the moment, but was in the intensive care unit in case he needed it later. It said Boris Johnson has asked Foreign Secretary Dominic Raab to deputize for him.

Hours before being admitted to the ICU, Boris Johnson had tweeted that he was in good spirits after spending a night in the hospital.

“On the advice of my doctor, I went into hospital for some routine tests as I’m still experiencing coronavirus symptoms. I’m in good spirits and keeping in touch with my team, as we work together to fight this virus and keep everyone safe,” Boris Johnson said.

The prime minister’s spokesman said Johnson had spent a comfortable night and remained in charge of government despite being admitted to St Thomas’ Hospital after Covid-19 symptoms of a cough and fever persisted.

Boris Johnson sent out a tweet thanking the National Health Service (NHS) for taking care of him and others in this difficult time.

Boris Johnson had been quarantined in his Downing Street residence since being diagnosed with COVID-19 on March 26 – the first known head of government to fall ill with the virus.

He continued to preside at daily meetings on the outbreak until Sunday and has released several video messages during his 10 days in isolation. Raab chaired the meeting Monday.