American rapper Eminem has apologised to singer Rihanna - through music - for siding with her ex-boyfriend, singer Chris Brown, more than 10 years ago.

Brown, now 31, made headlines in 2009 when a photo of his then girlfriend Rihanna's bruised face was released online.

Brown later pleaded guilty to assault and was sentenced to five years' probation and 180 days of community labour.

In November 2019, a seven-second clip of a song said to be written by Eminem but which was not released was leaked online. The lyrics included the lines "of course I side with Chris Brown / I'd beat a b**** down too".

Eminem's publicist Dennis Dennehy said to the media later that the rapper scrapped and rewrote the song after he recorded it.

Last week, Eminem, whose real name is Marshall Mathers, released a surprise album Music To Be Murdered By, which was followed later by the deluxe edition Music to Be Murdered By - Side B.

One of the songs in the album is Zeus with lyrics including: "But, me, long as I re-promise to be honest / And wholeheartedly, apologies, Rihanna, / For that song that leaked, I'm sorry, Ri / It wasn't meant to cause you grief. Regardless, it was wrong of me."

Eminem, 48, and Rihanna, 32, have collaborated several times on songs, including Love the Way You Lie from his 2010 album Recovery, Numb from her 2012 album Unapologetic and The Monster from his album The Marshall Mathers LP 2 (2013).