Charlize Theron is sick of rude reporters calling her "ugly".

The actress accepts she went out of her way to look unattractive to play lesbian killer Aileen Wuornos in Monster, but she was simply make-up-free for other roles for which she was dubbed ugly.

And now she's letting the media know that she'll no longer stand for rude questions about her looks.

She tells the new issue of W magazine: "You better not be bringing up ugly."

Theron insists she did nothing to play down her stunning looks in North Country or The Valley of Elah - two films in which her characters were called less than attractive.

She fumes: "North Country was dirt. That's what happens when you go into a mine. In The Valley of Elah - that's when I took real offence, because that was my real hair colour and me with no make-up."

The Oscar-winner is also annoyed by people who think she chooses "ugly" roles to win favour as a serious actress.

She says: "It really irks me that people think I choose these roles because, if I'm not looking attractive, they will take me seriously.

"I'm sorry, but if I'm going to play a cop I'm not going to be wearing eyeliner. I'm not going to wake up with lip gloss on, because that's not how women wake up, not even the most beautiful women." - Wenn