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When asked about Kendall's involvement in the underwear ads known for their sizzling, sexy campaigns, Klein revealed that he wasn't sure that the model was the best choice for the ad campaign.

Speaking during the event, he said:

“You know, I’m really not that familiar with it. I’m honestly not. I’m sure she’s a lovely young woman. It’s not the kind of thing I would have done, even today. Justin Bieber, yes.”

Klein went on to hail Justin Bieber who has played the role on numerous occasions, seamlessly, while calling out models for being booked based on their social media followership, taking a shot at Kendall's big sister, Kim K.

"When [I say] I like Justin Bieber in the Calvin Klein Underwear [campaign], it’s because I like him – not because he’s got millions of followers.

“Now, models are paid for how many followers they have. They’re booked not because they represent the essence of the designer, which is what I tried to do – they’re booked because of how many followers they have online. I don’t think that, long-term, is going to work. I don’t think that’s a great formula for success for the product you’re trying to sell.

“If you take really exquisite photographs of the right people in the right clothes in the right location, and you put it online, that’s fine. Just putting any old clothes on Kim Kardashian, long-term, isn’t going to do a thing.”

At this point, it is hard to tell if the brand owner simply has a bone to pick with the Kardashian women or this ad in particular.

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Watch video clip below: