It's a total rip-off of her earlier bum posing work!
Or at least, that's what Kelly's suggesting on Instagram.
We're not sure how far back in history we'd have to trawl to find the original inventor of the bum-out-chin-down pose, but we suspect, it may have kicked off a little before both Kelly and Kim's respective careers.
Not to be outdone in the pert butt stakes however, Kelly has fished out a snap from the Brook bum archives and copied Kim into a cheeky caption.
"@kimkardashian I've seen that shot somewhere before HA!!"
So what do you think? Ready for a Kim Kardashian vs Kelly Brook bum war? Gulp.
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