AceShowbiz - Lily Allen is nursing a sore backside - she was left "bleeding" after accidentally sitting on a metal barbecue spike. The "Smile" hitmaker was heading to an outdoor party at a friend's house on Monday, August 3 when she sat down on a stack of skewers in her car and received a nasty gash on her butt.

But the British singer saw the funny side of her embarrassing mishap - and shared her pain with her followers on Twitter.com. She writes, "Who goes to an 18 year old's birthday BBQ and skewers themselves in the a**e on the way? Note to self. Don't leave wayward tetanus ridden skewers on the car seat. Bleeding."

Lily Allen previously pulled out of several promotional pop appearances, citing ill health. The "Smile" hitmaker is due to take a hiatus from music later this year and has only a handful of gigs left before she begins concentrating on other business ventures, including the launch of her fashion boutique. She has been busy promoting a new duet with U.K. rapper Professor Green.