Britney Spears has unveiled a mysterious countdown clock on her website.

The date at the end of the countdown, which is entitled 'All Eyes On Me', is September 17.

The singer has been busy for a number of months working on the follow-up to her 2011 record 'Femme Fatale'.

It is unclear whether the countdown relates to a possible comeback single, or the unveiling of release dates.

However, producer Naughty Boy recently revealed that Spears' next single would land in the next "couple of weeks". He said:

"It was William Orbit who approached me to work on it and he is involved in the album. I'm just really excited about working with him as well as Britney. It's not out for another couple of weeks, but we've just started working on tracks for her until the studio session."