Katy Perryallegedly celebrated New Year's Eve with a man who was a dead-ringer for her estranged hubby, Russell Brand.

Following the shocking news that Russell had filed for divorce from the E.T. singer , Perry is said to have welcomed 2012 with a Brand look-a-like in Los Angeles, while the real Russell rang in the new year alone at a hotel in London.

According to the New York Post, the 27-year old was "in a great mood" as she partied with her male companion at Soho House in West Hollywood.

It is thought that the long-haired man chatted up Katy at the bash, with onlookers stating: "you wouldn’t have ever even known that her husband had just filed for divorce."

Another guest told the newspaper: "After midnight, Katy and a male friend got on the dance floor, twirling each other around and dancing holding hands."

While Perry let her hair down in LA, Brand spent New Year's Eve alone at the Savoy Hotel in London, with a source telling The Mirror: "He wasn’t up for celebrating and just ordered food to his room. The next morning he was in the gym from 11am and spent two hours there."

Reports claim when a gym goer at the hotel wished the 36-year old funnyman a Happy New Year, Brand replied: “Here’s hoping it gets happier.”

Russell could be in line to make £20million from the break-up as himself and Katy did not sign a pre-nup, meaning that under Californian law, he is entitled to half of her huge fortune.

It is currently unknown why Brand decided to divorce the Teenage Dream hitmaker, with some insiders claiming it could be due to Perry's reluctance to take time off work to have children.

CHECK OUT PICS OF KATY & HUBBY RUSSELL IN HAPPIER TIMES HERE

SEE SEXY PICS OF KATY PERRY HERE!