Rumours that Chris Brown is the mystery collaborator on Rihanna's 'Birthday Cake' were confirmed overnight, as the Bajan superstar unveiled the full-length cut of the track.

A shorter version had appeared on her latest album, Talk That Talk.

Brown's verse lyrics include: "Girl, I wanna **** you right now / Been a long time, I'm missing your body". Aww, what a gent.

Listen to 'Birthday Cake (Remix)' below:

What's more, Rihanna has returnedthe favour by appearing on Brown's new single 'Turn Up The Music'. She wrote on Twitter: "It's a download OVERLOAD!!! Working on more links for u guys, so err body could have some #CAKE (sic)"

Listen to 'Turn Up The Music (Remix)' below:

Rihanna and Chris Brown party together