Britney and Rihanna perform at Billboard Awards

Britney Spears transformed herself from a perfect princess to a pole dancer as she and Rihanna opened last night’s Billboard Music Awards in Las Vegas.

Britney Spears

Wearing knee-high boots and a black bodice, Britney wriggled about on the MGM Grand Garden Arena stage as she and Barbados star Rihanna performed the latter’s UK No.3 hit S&M.

The meagerly-clothed duo, who also held chains, then participated in a pillow fight with backing dancers as the sexy routine came to a close.

The 29-year-old Britney arrived via a ladder that rose from below the stage to join 23-year-old Rihanna midway through the hit song, with the noisy audience screaming in delight as the blonde singer removed a mask to strut about with the red-haired songstress.

As the routine progressed, Rihanna and Britney first faced each other and then writhed around two poles – sending the audience into further bouts of delighted yells.

Britney later returned to the stage to join rapper Nicki Minaj as the Trinidad and Tobago star performed recent single Til The World Ends.

While Toxic hitmaker Britney provided the biggest talking point of the evening, the ceremony really belonged to Eminem and Justin Bieber as the rapper and pop sensation each picked up an astonishing six awards.