Showbiz
The Blue Peter presenters slept together in a hotel after spending a day filming in London.
"He was lovely - warm, interesting and fun - and was between marriages," she told the Daily Mail.
"We were on an assignment out of London - neither of us can remember quite where - and we had a few glasses of wine at our hotel and one thing led to another."
Singleton, 71, added: "It was one of those impulsive, enjoyable experiences, but more a friendship thing."
The TV veteran decided to come clean about the romance after being quizzed about the subject by Anne Robinson on a Weakest Link special.
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