Explaining what caused him to make the controversial comments, he told The Observer: "I was very nervous and a bit confused but, yes, I made those remarks - which were inexcusable - but I made them in a totally jocular, ironic way. There was some polite applause and that was it, I thought. I thought everything was OK. No one accused me of being a sexist pig."
But within a few hours he had become the focus of a vicious social media campaign.
The biologist later issued a full apology, saying: "I am extremely sorry for the remarks... I accept that my attempts at a self-deprecating joke were ill-judged and not in the least bit funny."
Women scientists also rushed to his defence, including physicist Dame Athene Donald, biologist Professor Ottoline Leyser and physiologist Dame Nancy Rothwell. Yesterday, his wife, Professor Mary Collins, one of Britain's most senior immunologists who also has a post at UCL, said the couple had broken down following the news. "Tim sat on the sofa and started crying. Then I started crying. We just held on to each other," she said.
She denied that her husband was sexist, adding: "It was an unbelievably stupid thing to say. You can see why it could be taken as offensive if you didn't know Tim. But really it was just part of his upbringing. He went to a single-sex school in the 1960s. Nevertheless, he is not sexist. I am a feminist and I would not have put up with him if he were sexist."
Sir Tim has since been sacked from his post on the European Research Council's science committee and resigned from other posts, including membership of a Royal Society committee.
"I have become toxic. I am finished," he added. His wife said: "Tim was still on the plane from Seoul when a senior manager at UCL phoned me and said Tim had to resign his honorary position. They had not even spoken to Tim at that point.
"He just said Tim had to resign or we fire him. It was very upsetting. We are both extremely angry."
Yesterday, pictures emerged of Sir Tim visiting his alma mater, Clare College, Cambridge.
Asked if he was in discussion with them about a new role, he said "no, of course not".
UCL did not respond to requests for comment.
- Daily Mail