Lawyers for the royal family will appear in court Monday in Paris, where they will ask a judge for an injunction to prevent other publications from printing topless photos of Kate Middleton sunbathing.
The photos were first published in French magazine Closer and later ran in the Irish Daily Star. An Italian gossip magazine, Chi, has announced plans to run them next week in a special issue.
The magazine reportedly has 200 photos of the Duchess sunbathing on a balcony in France, according to TMZ.
The couple's lawyers will also seek damages.
"There can be no motivation for this action other than greed," a St. James Palace spokesperson told the BBC, in regards to the Irish publication.
Northern and Shell, the owners of the Irish Daily Star, said they disagreed with the newspaper's decision to publish the photographs of the Duchess of Cambridge and "very much regret the distress it has caused," The Associated Press reported.
The scandal blew up on Friday when Closer published a five-page spread of photos of what appears to be the Duchess of Cambridge, 30, on vacation, sunbathing, under the headline "Oh My God!"
Prince William and Kate Middleton have begun "legal proceedings for breach of privacy" against the magazine's publishers, St. James Palace said in a statement Friday, after calling the publication of the photos "a grotesque and totally unjustifiable" invasion of the young couple's privacy.
The magazine defended the decision to publish the photos, saying in a statement on its website that the photos would only appear in the French, not the British edition, and were not degrading.
The pictures were reportedly taken while Middleton and Prince William, who celebrated their one-year wedding anniversary in April, enjoyed a mini four-day vacation together last week at a secluded chateau in the south of France before beginning a tour of the Far East and South Pacific to celebrate Queen Elizabeth II's Diamond Jubilee.
The royal couple was reportedly told about the photos as they ate breakfast Friday before visiting a mosque in Malaysia. A palace source tells ABC News that at first the couple simply felt saddened, but as the day wore on the sadness turned to shock and anger and ultimately resulted in a decision to take legal action against the magazine.
"Their Royal Highnesses have been hugely saddened to learn that a French publication and a photographer have invaded their privacy in such a grotesque and totally unjustifiable manner. The incident is reminiscent of the worst excesses of the press and paparazzi during the life of Diana, Princess of Wales, and all the more upsetting to The Duke and Duchess for being so," the St. James Palace said an earlier statement Friday.
The revelation came just one day after Middleton marked an important first as a royal, delivering her first official speech overseas. The well-received speech was delivered to staff and patients at the Hospis Malaysia in Kuala Lumpur and focused on the importance of specialized medical care for seriously ill children. Middleton is a Royal Patron of East Anglia's Children's Hospices in England.