Pippa Middleton has had 3000 of her private photos stolen.

Pippa Middleton

Pippa Middleton

The 33-year-old author - who is the younger sister of Duchess Catherine - has had her Apple iCloud account hacked and an anonymous person is offering to sell the photographs to media outlets.

The seller promised pictures of her royal relatives including the Duke and Duchess of Cambridge's children Prince George and Princess Charlotte as well as photos from parties, wedding dresses and "everything in between", the Mail Online reports.

The seller told journalists: "Due to current climate on privacy laws in the UK I'm intending a quick US sale but would at least give you a heads-up ...

"This is obviously a vast source of info and pictures that I neither want nor intend to keep in my possession very long."

A spokesman for Pippa has confirmed action will be taken over the images.

They added: "Miss Middleton's lawyers have been informed and, in due course, the police will too."

Pippa - who recently got engaged to hedge fund manager James Matthews - is not the first celebrity to get her account hacked.

Jennifer Lawrence, who had personal photos stolen, admitted she was left feeling "afraid" when intimate pictures were shared with the world.

She said at the time: "I was just so afraid. I didn't know how this would affect my career ... I can't even describe to anybody what it feels like to have my naked body shoot across the world like a news flash against my will. It just makes me feel like a piece of meat that's being passed around for a profit.

"Just because I'm a public figure, just because I'm an actress, does not mean that I asked for this. It does not mean that it comes with the territory. It's my body, and it should be my choice, and the fact that it is not my choice is absolutely disgusting. I can't believe that we even live in that kind of world. People forget that we're human."