The 51-year-old quit her role on the popular Channel 4 quiz in 2008 after reportedly being asked to take a 90% pay cut or stand down.
"I offered an olive branch," Vorderman told the Radio Times. "I said I'd be happy to turn up at their 30th anniversary bearing in mind I was the first woman on the channel. Nothing."
Following her departure, Vorderman claimed that she was banned from visiting the Countdown set.
"I was told in no uncertain terms that I was never allowed back in the studio," she revealed. "I still don't understand it."
Rachel Riley replaced Vorderman in 2009, with The Apprentice star Nick Hewer having served as her co-host since January of this year.
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