Topless images of Catherine 'sadden' royals

Just weeks after the scandal about pictures of Britain's Prince Harry naked in Las Vegas, a magazine has sparked fresh controversy by publishing pictures of Prince William's wife, Catherine, topless while vacationing.

The duchess of Cambridge is "upset" with the magazine -- a French publication called Closer, a royal source told CNN. Palace officials, threatening legal action, have blasted what they call a "grotesque" invasion of privacy.

The grainy pictures appear to have been taken with a long camera lens while the couple was staying at a private chateau in Provence, in southern France.

They were "hugely saddened to learn that a French publication and a photographer have invaded their privacy in such a grotesque and totally unjustifiable manner," a St. James's Palace spokesman said.