Britney Spears promises her new album will keep fans on the "edge of their seat".

The singer - who releases LP 'Circus' on her 27th birthday, December 2 - revealed her latest material is a return to her pop roots and will "engulf" anyone who hears it.

She said: "I can't wait to share it with my fans. I worked with producers from some of my earliest albums - I went old school.

"I called it 'Circus' because I like the fact that you are on the edge of your seat when you are at a circus. You are never bored. You are engulfed in what is going on and you want to know what is going to happen next."

Britney says 'Circus' has a totally different sound to her previous album 'Blackout', which she recorded when she was going through a "dark phase" in her life.

The 'Womanizer' star explained: "They are two different vibes. 'Circus' is a lot lighter than 'Blackout' and has more pop in it. 'Blackout' is darker, edgier and a little bit more urban. When I recorded 'Blackout' I was going through a really dark phase in my life and a lot of the songs reflect that. I didn't go on tour with that album so I will be bringing some of the songs from 'Blackout' on tour with me next year."

Britney also revealed her favorite song on the LP is the title track because it symbolizes her love of performing.

She added in a video interview on britneyspears.com: "The song 'Circus' is about me as an entertainer, about what I do and what I bring to a show is like a circus. I bring costumes and fun and theatrical things that leave people awed. I tell a story on stage and there won't be elephants in my show but it has the same elements as a circus."