Britney Spears concluded the North American leg of her Circus tour with two raunchy shows in Las Vegas - where she performed a lap dance for singer Lance Bass.

The pop star wrapped up her seven-month tour in Sin City on Sunday and gave fans a thrill by inviting the 'N Sync star - her friend and former tour mate - to join her onstage at the Mandalay Bay venue. Spears proceeded to serenade him while writhing seductively to her track Breathe On Me, while Bass could be seen singing along.

Barry Manilow was also in the audience, while former Spice Girl Melanie Brown and teen sensation Miley Cyrus were in town to catch Spears' concert on Saturday. And Spears was clearly delighted with the star-studded turnout - she later contacted Cyrus on Twitter.com to tell her: "Thanks for coming to my show last night! Hope you had fun! - Britney."

Excited Cyrus responded, "You are very welcome. I love you so much!"

The Toxic hit-maker will relax throughout the month of October before flying to Australia to play a string of dates Down Under in November.

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(This news article provided by World Entertainment News Network)