Sinitta says the late Princess Diana had "the most delicious sense of humour."
The 53-year-old singer first met the late royal - who tragically died in a fatal car crash in Paris in 1997 at just 36 years old - at the luxury health and fitness club The Harbour Club in London, and has said the pair were often referred to as a "double act" by other club members.
Speaking to Hello magazine ahead of the 20th anniversary of Diana's death - which will be marked in August this year - the 'So Macho' hitmaker said: "We made friends at the Harbour Club and shared the same personal trainer. What Diana and I had most in common were the same friends in the club. Both of us were also ballet trained, so we would always have a chat on our own on the mats in the stretching area.
"Our friend Christopher Whalley used to call us Ebony and Ivory, as if we were a little double act! Diana was extremely fit, more fit than her fragile frame would have you imagine.
"I also used to like to tell her the gym gossip and make her giggle - we had nicknames for a lot of the regulars. She had the most delicious sense of humour!"
Now, the 'Toy Boy' singer is an ambassador for the Diana Award, a charity which was established in the late Princess' name in 1999 to support young people's ability to change the world.
This year, the Diana Award will honour the 20th anniversary of Princess Diana's death by launching a number of initiatives throughout the year aimed at promoting the late Princess' qualities of kindness and compassion.
Princess Diana's two sons, Prince William, 34, and Prince Harry, 32, are also expected to take part in a selected number of the planned events, which will include a National Kindness Day - where people are encouraged to do something nice for the sake of another - in March.
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