London -The publication by a French magazine of topless pictures of Prince William's wife Catherine is "grotesque and totally unjustifiable", their office St James's Palace said on Friday.
The couple, officially known as the Duke and Duchess of Cambridge, were particularly upset because it was reminiscent of the press treatment of William's late mother Diana, Princess of Wales, it said.
"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 palace said in a statement.
"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.
"Their Royal Highnesses had every expectation of privacy in the remote house. It is unthinkable that anyone should take such photographs, let alone publish them.
"Officials acting on behalf of Their Royal Highnesses are consulting with lawyers to consider what options may be available to The Duke and Duchess."
The French version of Closer magazine on Friday printed grainy photos showing a fit Catherine wearing just the bottoms of a black and white bikini while on holiday with William at a private house in Provence in the south of France.