The Hills star Heidi Montag has hinted she's not the only girl on the hit reality TV show to have undergone cosmetic surgery in a blast aimed at her castmates.

Montag has confirmed she had a breast augmentation and nose job last April, and she's upset with criticism she's had from fellow The Hills stars.

Montag insists at least she came clean about her plastic surgery, and she tells Maxim magazine she wishes others on the show would do the same.

She says, "They were saying malicious things about me, and I was like, 'You guys are hypocrites.'

"Almost everyone on the show has had some kind of surgery."

That comment has prompted new speculation fellow The Hills star Audrina Partridge has had a boob job.

She tells Life + Style magazine, "There are so many rumours. It's entertainment, so I can't take it to heart."