She’s barely said “I do,” but royal newlywed KATE MIDDLETON is already embroiled in a shocking sex tape scandal!

British authorities have launched an in­vestigation into high society orgies thrown by a friend of Kate, fueling lurid rumors that Prince William’s bride attended a sex party and may have been recorded in a compromising situation!

Close pals of the queen-in-waiting insist the devastating rumor is hogwash, but the mere accusation has stunned the royals, who are deathly afraid of a sex scandal.

The orgies have been staged by Emma Sayle, an old school friend of Kate and a notorious British sex merchant.

Palace insiders are outraged and terrified that a tape or pic­tures could surface. Even if they’re fakes they will destroy Kate’s squeaky-clean image and jeopardize the future of the entire royal family.

When Kate heard whispers she’d been captured on acell phone camera, “she just laughed it off,” divulged a royal insider. “She denied ever going to an orgy.”

The scandalous high society swing parties run by Kate’s pal Emma are known for their anything-goes masked parties.

Now Emma is announcing a “Royal Fling” is being held just one week after the April 29 wedding.

The Queen is horrified over what she’s hearing about Kate. Everyone knows Kate has a reputation for her love of partying, say sources.

 “She used to be out until the wee hours at all the most exclusive clubs and parties in London – mixing with the sort of upper-class types attracted to Emma’s sex club,” disclosed the royal insider.

“When she broke up with William for a while because he wouldn’t commit, she put on her sexiest dresses and hit the London club scene hard. Don’t forget, it was Kate’s sexy see-through outfit at a college fashion show that caught his eye in the first place.”

Emma and 29-year-old Kate went to the same expensive private school and have re­mained friends.

Emma’s members-only sex club, named the Killing Kittens,says its sole aim is the pursuit of female sexual pleasure – and the women are the only ones allowed to approach other guests for sex.

All the details are in the new ENQUIRER!