Boris Johnson needed a “significant level of specialist treatment” at the worst points of his battle against coronavirus, according to his spokesman.
The PM left hospital over the weekend, having previously been in intensive care at one point of his stay.
Mr Johnson has now tested negative for Covid-19, the spokesman confirmed, and is recovering at Chequers.
“Now, clearly, if a person is moved to intensive care, that means that they are requiring a significant level of specialist treatment,” the spokesman said.
“So, I think it was clear from the moment the Prime Minister was moved to intensive care that his condition had worsened.”
He would not go into further details of just how ill the Prime Minister had been.