BOOB OUT!

Cheryl Cole flashes a boob at her concert afterparty

Breast dressed ... Cheryl sizzles in little black dress that shows off her boob

was the breast dressed guest last night at a party to celebrate her stunning show at London's O2 - sporting a little black frock that almost exposed her left boob.

Pop royalty turned up to toast the singer at London nightclub Whisky Mist, including Nicole Scherzinger, Will.i.am and Cheryl's Girls Aloud bandmates Kimberley Walsh and Nicola Roberts.

But all eyes were on the 29-year-old, who almost spilled out of an asymetrical mini-dress that showed off her perfect pins and barely covered her assets.

Cole lotta love ... Cheryl was accompanied by beau Tre Holloway

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Even the presence of Cheryl's former nemesis Nicole couldn't dampen her spirits after a dazzling performance - the latest date of her A Million Lights tour.

After bringing the house, Cheryl tweeted: "LONDON THE ROOF WAS ON FIRE !!!!!!!!!!! #ProudSoldier"

Busting out ... Nicole Scherzinger dazzled in a gold dress

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The Pussycat Doll famously replaced Cheryl as a judge on The X Factor USA last year.

And she threatened to upstage her British rival again, arriving arm-in-arm with Cheryl's BFF Will.I.Am - with her boobs bulging out of a glistening gold mini-dress.

Where there's a Will ... Nicole and Will.i.am

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The fashion face-off totally overshadowed Nicola Roberts - who was also celebrating her 27th birthday last night.

But the singer - who stepped out in a bizarre tweed trouser suit - seemed happy to let her bandmate take the spotlight.

After a birthday shopping spree with her boyfriend Charlie Fennell, Nicola headed to the O2 with Kimberley to watch their bandmate on her big solo night.

Suits you ... Nicola's odd tweet outfit

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And the pair were thrilled for their pal.

Nicola tweeted: "I am so so so so proud right now.. wiping tears @CherylCole #AMillionLightsTour pic.twitter.com/mLJavKze"

Kimberley added: "so unbelievably proud of @Cherylcole right now!!!!!!!!! Love her tooooooo much! #amillionlights"

Walsh and go ... Kimberley arrives at the bash

Read more: http://www.thesun.co.uk/sol/homepage/showbiz/4577810/cheryl-cole-breasts-nicola-roberts-birthday.html#ixzz28iMB7ws6