UK prime minister Boris Johnson underwent a scheduled operation on his sinuses on Monday morning, June 20, Downing Street has said.

It was described as a “very minor routine operation” under general anaesthetic at a London hospital.

Mr. Johnson, who turned 58 on Sunday, is resting at home and is planning to chair Tuesday morning’s Cabinet meeting and travel to a gathering of Commonwealth leaders in Rwanda later this week.

“He went to hospital around 6am and the operation was carried out first thing this morning,” the prime minister’s official spokesman said. “He was back in Downing Street shortly after 10am.”

Asked how Mr. Johnson was feeling, the spokesman said he had not spoken to him since his return to his official residence but that he was resting there.

The timing of Mr. Johnson’s return to work would depend on how he feels, said the spokesman.

Asked who was in charge of the UK nuclear accounts during the procedure, the spokesman said Deputy Prime Minister Dominic Raab and Cabinet Secretary Simon Case were aware in advance and that Mr. Johnson was under for a “relatively brief time”.

Procedures were in place so that any significant decisions could be deferred to Mr. Raab before Mr. Johnson resumed duties, the spokesman said.

The operation was by the UK’s state-funded National Health Service and was scheduled “for a while”, he said, without specifying at which hospital it took place.

Mr. Johnson’s sinus issue was not said to be related to his Covid illness two years ago.

The prime minister spent several days in hospital intensive care in April 2020 after contracting Covid, calling it “a tough old moment” that “could have gone either way”.