Keira Who?

Britney Spears has hit back at actress Keira Knightley for slamming her infamous flashing underwear incident.

The Pirates of the Caribbean star branded Spears a "slut" after she was photographed flashing her underwear earlier this year (07).

But the singer laughed off the comments, adding, "Who's Keira Knightley? I guess she must need the publicity".

OH SNAP!We all know Keira likes to dish it out, who knows if she can actually take it.
SOURCE