FERGIE'S AMAZING TANTRUM AS ANDY CHATS UP BEAUTIES; Stunned celebrities witness astonishing royal bust-up - Jealous Duchess storms off in huff at Palace.
The fiery duchess shook with rage and stormed off in a huff when Andrew flirted openly with Anna Kournikova, Liz Hurley and Claudia Schiffer at a star-studded charity tennis bash.
But the final straw was when the prince laughed and joked with old flame Koo Stark right in front of her.
To the amazement of hundreds of watching celebrity guests, furious Fergie, 40, marched off with her daughters Beatrice and Eugenie - her face bright red with anger.
She didn't even wait to see the end of the tennis tournament - which featured a match between John McEnroe and Bjorn Borg and raised thousands of pounds for charity.
One stunned onlooker who witnessed the amazing tantrum said last night: "Fergie went berserk when Andrew started chatting to the girls during a rain break.
"They were all lined up - some of the most famous and beautiful women on the planet - and he couldn't resist. He kept staring at Anna Kournikova who looked amazing in a very revealing short blue dress.
"He was mesmerised by Liz Hurley who kept crossing and uncrossing her legs.
"He also started laughing and joking with Koo and that really made Fergie look daggers.
"You could almost see the tension reaching explosion point between them.
"The minute the McEnroe-Borg match was finished she took her daughters by the hand and stormed off.
"Her face was like thunder and she was clearly furious.
"Everybody expected her to stay for a doubles match involving Anna Kournikova and French star Henri Leconte because Bea and Eugenie were enjoying it so much but she was determined to leave. Andrew looked very sheepish after she'd gone and stopped wise-cracking with all the beauties.
"He seemed to know he had stepped out of line. He and Fergie had obviously had one hell of a row and she made her feelings very plain indeed."
Fergie's jealous outburst reveals once again the deep feelings Andrew inspires in her.
Despite the fact the couple were divorced four years ago, they still live in the same house and Andrew, 40, has even talked about the possibility that they will get remarried one day.
But the prince is also well known as a ladies' man. In the past couple of years, he has been linked with French beauty Audrey Rimbault, supermodel Caprice and Aussie PR stunner Emma Gibbs.
It was only natural that "Randy Andy" would make a bee-line for the beautiful women at the tennis tournament - sparking Fergie's fury.
One royal source said last night: "Andrew and Fergie still have a kind of magic hold over each other. She gets deeply upset when he so much as talks to other women.
"And deep down Andrew still loves her as the mother of his children and best friend.
"He was mortified after she walked out of the tennis and realised that laughing and joking with beautiful women right in front of her was insensitive.
"Jealousy is rarely far away in close relationships like theirs and the duchess was eaten up with it at the tennis."
Andrew was the brains behind the special Buckingham Palace tennis event which raised cash for his favourite NSPCC charity. Guests paid up to pounds 2,500 each to see McEnroe beat Borg in a repeat of their famous Wimbledon matches.
Although Fergie had spent the previous weekend with her 50-year-old boyfriend Italian count Gaddo della Gherardesca, she obviously thought she should be by Andrew's side for such an important occasion.
It was because she took the event so seriously that she was so upset by Andrew's behaviour.
The royal source added: "This was a big day for Andrew and Fergie was pleased to be by his side to support him through it.
"She was very upset that he seemed to take for granted all the effort she put in and spent the day eyeing up pretty women."
Andrew appeared to have learned his lesson later last week when he and Fergie went out together to a garden party hosted by Sir David Frost.
The source said: "He was on his very best behaviour and his eye didn't rove once."
For more on Andrew and Fergie, try: royalty.about.com