The interview from 1986 revealed how the pair had fallen in love after just nine months after meeting each other.
Sarah and Prince Andrew divorced in 1996 – but ten years earlier, the young royal couple appeared to be heavily in love in an exclusive engagement interview with broadcaster Anthony Carphew.
At the beginning of their ITV interview, Prince Andrew recalled the moment he asked Fergie for her hand in marriage.
He said: “I asked Sarah some weeks ago and Sarah said yes. Which surprised me.
“Here’s a little anecdote for you – she said ‘when you wake up tomorrow morning, you can tell me it’s all a huge joke’.
And a smiling Fergie quipped: “I’m sitting here.”
During the interview the loved-up couple described themselves as “a good team” and “solid friends”.
Mr Carphew asked: “When did you both know it was the real thing?”, to which Andrew replied: “It was probably the end of the last year, before Christmas perhaps. And it just carried on from there.”
The Duke and Duchess of York were married for 10 years, and they were both close to Princess Diana, whose marriage to Prince Charles had been publicly showing signs of strain.
During the ITV interview, Sarah Ferguson spoke of her blossoming friendship with Diana.
Fergie said: “The Princess of Wales and I are extremely good friends and naturally, we talk about different subjects.
“We are very, very good friends.”
In 2017, a body language expert analysed the Duke and Duchess of York’s engagement video to dig deeper into the truth about their relationship.
Body language expert Judi James studied the pair’s body language, pointing out that the interview showed a very different side to royal romance – at the time of their royal engagement, Andrew’s brother Princes Charles’ marriage to Princess Diana had hit a publicly rocky patch.
Mrs James claimed the fun facade of the Andrew and Sarah may have been more indicative of early signs of trouble than ease and comfort with one another.