'Confident' singer Justin walked out on stage to present with model Lara Stone but wasted no time in taking off his clothes after getting jeers from the crowd inside the Barclays Centre in Brooklyn.
Rather speedily, Justin whipped off his light blue blazer, followed by his trainers and jeans.
Continuing to get a mixture of boos and cheers, Justin then picked up the mic from the floor and asked the audience: "Is that better?"
Seemingly it wasn't, as within seconds, Justin passed the mic back to Lara before taking off his black vest to show off his six-pack and tattoos on his torso.
Clearly a treat for fans, many whipped out their mobile phones to capture Justin in the flesh!
Standing in just his black and red boxers, the 20-year-old then continued to present the show, where he introduced a performance from Rita Ora. Justin was then seen flexing his muscles and holding his hands on his hips to humour the crowd.
Joking about his stripping antics on stage, Justin later said on Twitter: "Grandma always said kill 'em with kindness... and then strip on live national TV. Lol."
He continued: "Good times tonight. Thanks for having me tonight #FashionRocks. #mycalvins :)."
Posting a photo on Instagram, Justin added: "Just stripped on national television. Hahahaha it wasn't planned lmao." The photo racked up more than 700,000 likes and sent his loyal fans - Beliebers - into a frenzy.
Fashion Rocks is an international charity fundraiser event, and the night saw a string of stars show their support including Jennifer Lopez, Nicki Minaj, Usher and Pitbull.
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Watch Justin's video for 'Confident' below: