Dr Fry - who co-presented The Great British Intelligence Test and a Coronavirus Special alongside Mosley - spoke about his "extraordinary" actions on The One Show.

She lent her voice to the host of celebrities who have paid tribute to the TV doctor, who was found dead on the Greek island of Symi four days after he went missing.

The body of the 67-year-old, who was a familiar face thanks to his regular appearances on TV programmes including The One Show, was found close to a cave complex beside Agia Marina around 10m from the sea.

Foul play has been ruled out by local police, who say there were no signs of injury and CCTV footage clearly showed no one was with him when he appeared to fall close to where his body was found.

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Speaking on The One Show Dr Fry said: "There was this rumour going around that once Michael had saved somebody's life in the office.

"I went and approached him about. I was like, 'Tell me, is this true?' And he sort of brushed it off, but it was completely true. Somebody collapsed in the BBC offices, in the corridors, and he saw them collapse.

"He went over and performed CPR on them for half an hour until the emergency services arrived and saved her life.

"She's gone on to have two children. I mean, this extraordinary thing… You know, if it was me, I think I'd be introducing myself and first thing I'd say is, 'Did you know I saved someone's life?' but for Michael, it was just part of it."

The One Show presenter Alex Jones also shared her own tribute to Mosley - who first appeared on the BBC flagship show in 2007 - saying he will be "sorely missed".

Jones said: "His death has been felt by millions of people all around the world who regarded him as their doctor.

"He was a super generous man. Even when he'd come on here in my early days when I was a bit shy, you always felt in such safe hands and he was so generous with tips and tricks, anything you wanted to talk about."

Mosley's widow, Dr Clare Bailey Mosely, paid tribute to her husband on Sunday, saying it was a comfort to the family he "very nearly made it" to safety.

She said Mosley - who went missing on Wednesday after leaving his wife and friends at Agios Nikolaos beach to walk back to their hotel - appeared to have undertaken an "incredible climb, took the wrong route and collapsed where he couldn't be easily seen" by search and rescue teams.

His body was discovered by a cameraman on Sunday morning after a widespread search by emergency services operating in dangerous conditions and high temperatures.