Britney Spears has revealed her happiness at seeing Shakira and Rihanna duet.

The two singers teamed up for the track 'Can't Remember to Forget You', which was released earlier this week.

It is due to feature on Shakira's upcoming new album and its unveiling followed weeks of rumours.

Speaking on Twitter, pop princess Spears said that the collaboration was a long time coming. She said:

"#nowplaying @shakira & @rihanna 'Can't Remember to Forget You'....love it! So glad you ladies joined forces!"

Despite the blockbuster collaboration credentials, 'Can't Remember to Forget You' only charted at No.12 in the UK midweek update on Wednesday (January 15).