Britney Spears has teased her fans by confirming that she is rehearsing for something "top secret".

The former X Factor USA judge has been working for months on her eighth studio album and it seems new material is imminent.

She recently launched an online countdown clock for September 17, which is when her new single is expected to be unveiled.

Speaking on Twitter, Spears has now suggested that she could be rehearsing for the song's video shoot. She said:

"Taking a quick break to say hi to all my tweeps :) Rehearsing for something top secret happening next week... #WERK."

Spears then replied to a fan asking if the project in question is her next single's video shoot by simply typing a winking face.