Kardashian: I told Montag to do 'Playboy'

Kim Kardashian has revealed that Heidi Montag sought her advice before agreeing to pose for Playboy.

The Keeping Up With The Kardashians star, who has previously stripped for the men's magazine herself, admitted to MTV News that she told Montag to "go for it".

"I was in Mexico and I got a call from Heidi saying, 'Call me right now'. She had said to me, 'What do you think? What's your opinion on if I were to do Playboy?'" she explained.

"I think that now's the time. I think it's a very classy magazine. It's artsy. I talked her through the whole process and helped her make up her mind."

Kardashian went on to say that Montag's husband and Hills co-star Spencer Pratt was also instrumental in her decision.

"They felt like it was the right thing for her to do and I'm anxious to see it... I'm excited to see what the pictures will turn out to be," she said.

Montag is reported to have posed for the September issue of Playboy, which will hit newsstands in August.