And it seems she might put off having kids until then.

"I couldn’t have them in the situation I’m in now but it’s definitely something I see for myself if I do do something else," she says.

Keira recently revealed she wants a "life" instead of stardom.

The 22-year-old told Elle magazine the pressures of fame have become too much.

"The celebrity thing is completely crazy. I think I just have to move away or give it up altogether," she said.

The star added that she reached her decision after a trekking holiday in the Himalayas.

"I spent 10 days in a place where no-one knew me or cared what films I’d been in," she said. "I got to have some total peace and balance and see myself as a tiny insignificant speck - something I really needed."

Keira is stripping off - May 13 2007
Actress Keira Knightley says she is stripping off on screen so often that film fans will soon be pleading with her to keep her clothes on.

"I have certain tools. One of them is my body," she told Total Film magazine.

The 22-year-old is currently shooting The Best Time Of Our Lives with Sienna Miller, about two women who enjoy a relationship with Welsh poet Dylan Thomas.

And she is soon to appear in Silk, an adaptation of the erotic novel by Alessandro Baricco set during the 19th century. "There are plenty of sex scenes in the book, so the adaptation is true to its source," Knightley said of her role in the film.

"I think soon, people are going to insist I keep my clothes on.

"I wouldn’t do anything I didn’t feel completely comfortable with. I suppose I’m very European in my attitude to my body. I’m an actress. I have certain tools. One of them is my body. I don’t mind stripping off occasionally."

Knightley will next be seen opposite Orlando Bloom and Johnny Depp in the third Pirates of the Caribbean film, which opens later this month.

Merchandising for the movie includes a toy figure of her character, Elizabeth Swann. But Knightley said: "It’s nothing like me."

The star of Bend It Like Beckham and Pride And Prejudice recently claimed she may quit the movie business because she is tired of fame.

And she told Total Film: "The pressure the entertainment industry puts on young women is sick. And it’s not so much what pictures they print or what they say. It’s a young woman being followed around by five men who could be anyone and you have no way of telling who they are - if they are actually legitimate photographers or in fact potential rapists. It’s terrifying."

Keira: I wish I was like Sienna - May 8 2007
Keira Knightley has apparently admitted she envies new co-star Sienna Miller’s "party personality" - and wishes she had more to say at glam showbiz events.

The 22-year-old, who was due to start filming The Best Days Of Our Lives alongside Sienna yesterday, is quoted by the Daily Express as saying: "At parties I can never think of a thing to say.

"I wish I was Sienna Miller. I watch that girl and she’s fabulous. She talks to everyone and laughs and smiles. When I talk to her, I hope a bit of her party personality will rub off on me but it never does."

The Pirates Of The Caribbean star added that she also feels out of place on the red carpet.

"I’ve become phobic about the red carpet because you just get so scrutinised and all I think is, I’m going to be in the Top 10 worst dressed list tomorrow.