Gwyneth Paltrow's racy red carpet emergency

Gwyneth Paltrow at the Iron Man III premiere. Photo/AP

Gwyneth Paltrow sent her assistants scrambling for a razor after realising how revealing her red carpet dress for the Iron Man 3 premiere was.

The 40-year-old actress wowed onlookers on Wednesday when she sported a striking full-length gown with sheer side panels by British designer Antonio Berardi to promote the film.

See: Paltrow and her fellow Iron Man III stars at the film's premiere.

Paltrow says she was forced to do some last-minute personal grooming before donning the sexy outfit.

"I kind of had a disaster," she told US talk show host Ellen DeGeneres.

"I was doing a show and I changed there and I went I couldn't wear underwear. Well, let's just say everyone went scrambling for a razor. I work a '70s vibe. You know what I mean?"

The "disaster" fell on the same day Paltrow was named People magazine's most beautiful woman in the world. The irony of the situation wasn't lost on the actress.

"I went from being the most beautiful to the most humiliated. In one day," she said.

Paltrow went on to add that she is still incredulous of her "most beautiful" title. The actress thought her long-time publicist Stephen Huvane was joking when he sent her an email about it.

"I re-read it three times. I was like oh, he sent this to the wrong client. Like there's no way," Paltrow said.

"It was actually psychologically interesting because for a minute I really thought that someone was playing a joke on me. I talked about it with my shrink."

- Cover Media