The 'Muppets' actress can't understand why the fashion house asked her to star in a campaign for their Opium fragrance - which saw her dodging a leopard while wearing towering high-heeled shoes - because she looks "so un-French".
She said: "God, I'm so un-French in that trailer."
Asked why she was invited to front the campaign, she added: "I don't know. I've no idea. Perhaps there was no one else?
"They made a mistake, a terrible mistake."
Despite her reservations, Emily admitted she finally said yes to the campaign after years of turning down beauty advertisement offers because she liked the "aura of scandal".
She said: "I think that I've been wanting to make sure that when I did it would be the right thing. There's such an aura of scandal around this perfume that I was quite attached to the idea of doing it from the word go. I'd been asked to do a couple of things but none were as classy as this. And I got to work with a leopard.?"
The 'Devil Wears Prada' star also revealed she wanted to wear a flowing gown instead of a tuxedo in the advert, but was advised it would send the leopard "crazy".
She told the Daily Telegraph newspaper: "I got word back that the leopard trainer says, 'If you have flowing fabric around the leopard the leopard will go crazy .' So I said yes to the tux."