Pop star Lily Allen suffered an embarrassing wardrobe malfunction during a gig in London when she accidentally flashed a nipple.

The Smile hitmaker wore a pink chiffon crop top with sequined trousers during her performance at the Shepherd's Bush Empire on Monday (28Apr14).

While she was mid-song, Allen clutched her chest and unwittingly made the top ride up, exposing her left nipple.

Despite the mishap, the singer seemed in great spirits and celebrated with an afterparty at a warehouse in U.K. capital, later writing on Twitter.com, "Thanks Red Bull Zero for throwing me a great party, I don't remember this but I was, indeed, dancing on tables."