Britney Spears has lashed out at Keira Knightley after hearing that the British actress voiced her disapproval over starlets who flaunt their lady bits at photogs on nights out.

As Entertainmentwise reported, Keira revealed her distain for Britney et al’s undercarriage-flashing antics.

 “They’re real people proving they’re sluttier than everybody else because they don’t even wear knickers,” Keira told Empire.

When told of the disapproving remarks, Britney went for the dismissive approach and responded with “Who’s Keira Knightley?”

When it was explained that Keira is a world-famous actress, the popwreck - displaying a breathtaking of lack of self-awareness - replied: “I guess she must need the publicity.”