(Cover) - EN Showbiz - Katy Perry was reportedly in a "great mood" on New Year's Eve.

The star spent Saturday night partying with friends in Soho House in West Hollywood.

Her husband Russell Brand filed for divorce the day before. However, Katy was determined to ring in 2012 with a smile on her face.

"Katy was in a private room with a group and she seemed to be in a great mood. She spent most of the night dancing and laughing with friends," a source told the New York Post.

The spy also revealed that the singer appeared to be enjoying her newly single status.

Katy was spotted chatting and flirting with a mystery man.

"One wouldn't have ever even known that her husband had just filed for divorce," the source added. "At one point, she was talking to a guy with long hair down to his shoulders in the hallway. They were talking for a while. She was smiling and leaning up against wall."

During the evening the star thanked the DJ for playing her hit record Friday Night. She counted down to midnight with her friends and then took to the dance floor to celebrate the event.

"After midnight Katy and a male friend got on the dance floor, twirling each other around and dancing holding hands. She looked like she was having a great time."

Meanwhile, Russell spent New Year's Eve back in London at a luxury party at the Savoy Hotel. He was spotted leaving the party with a group of friends including singer, Florence Welch.

"I'm doing good," he said. "Everything is going to be better next year." (C) Cover Media