Kate Middleton SUES France's Closer Magazine Over Topless Pics

Kate Middleton and Prince William have declared war on the French magazine that published naked photos of the future Queen of England -- filing a lawsuit today against the publication.

A rep for St. James's Palace released a statement saying that "legal proceedings for breach of privacy have been commenced today in France" by the royal couple.

So far, it's unclear what relief they are seeking.

As we reported, the family had threatened legal action over the topless photos published today by France's Closer magazine, showing a topless Kate on vacation with Prince William recently.

Now, they've made good on their word.

Moments after the pic went public, the Royal Family issued a statement, claiming, "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."

For the magazine's part -- Closer's editor Laurence Pieau has spoken out, calling the media "hypocritical" for condemning her decision to run the pictures.