Mary-Kate and Ashley OlsenMary-Kate and Ashley OlsenMary-Kate and Ashley Oslen have rattled someone's cage.

And now the twins are in for a shock.

The twosome are the targets in a new ad campaign.

And Peta are the ones behind it.

They're unveiling their latest advert right by the twins' Walk Of Fame star on Hollywood Boulevard.

Which probably won't make the girls too happy when they see that they've dubbed the pair The Trollsen Twins - for wearing fur and including it in their collections, Elizabeth And James and The Row.

Peta released a statement saying: "Thin-twins Mary-Kate and Ashley Olsen are about to get some publicity that will have them running away faster than if they'd spotted a calorie.

"No one would argue that Mary-Kate and Ashley could use some meat on their bones, but the last thing they need is hair on their backs."

The new ad has the rather blunt headline of "Fur Is Worn By Beautiful Animals And Ugly People".

To coincide with the ad, Peta have also launched a new web site devoted to "Hairy-Kate" and "Trashley" with the campaigners' unique twist.

Click on to see the Olsen twins' ad, along with the celebs who have supported rather than upset the campaigners in our gallery of celebrities and Peta.