Renee Zellweger set tongues wagging as she danced the night away to live Billy Joel hits with a mystery man.

The Bridget Jones star looked smitten as she shimmied up close to her handsome partner.

Uptown Girl: smiley Renee grabs her date for a dance

Zellweger, 38, has been rumoured to be dating an agent at Hollywood firm CAA - and onlookers speculated her man for the night was one and the same.

The pair were attending the outdoor Social@Ross concert in East Hampton, New York, with other stars including Mary-Kate Olsen.

Zellweger spent part of the night with actor Alec Baldwin, before grabbing her mystery man for Joel's encore of Piano Man.

Boogie night: Renee takes to the dancefloor and flirts with her date at the New York concert

Since her marriage to country singer Kenny Chesney was annulled in December 2005, Zellweger has not gone public with any romances, but she has been linked with Beverly Hills 90210 star Luke Perry.

Whoever her man was, he was certainly impressing the actress with his moves.

Saturday's ￡2,000-a-ticket concert, also a school fundraiser, was part of a series that opened with Prince and will finish with Tom Petty on 25 August.