Britney Spears celebrated her 27th birthday early on Saturday night at Britain's premier gay club.

The pop star, in London for an appearance on TV talent show X Factor, stopped by the G.A.Y. event, where she was presented with a cake, decorated to look like the cover of her new album Circus, which is released on her birthday.

Fans serenaded the singer with Happy Birthday as she beamed down from a V.I.P. balcony.

The big night was a Britney-themed party at the popular club, housed at London's Heaven venue.

After her whistle-stop European tour, Spears will now head back to the States for a birthday morning performance on U.S. TV show Good Morning America.