He was referring to a decade-old song that leaked in 2019, on which he said "of course I side with Chris Brown".
On a song off his new album, Eminem has apologised to Rihanna over a lyric he rapped in a song that was released last year.
The song, which only saw the light of day last year, was actually recorded 10 years ago, and it heard the Detroit artist rap "of course I side with Chris Brown".
On his new song 'Zeus', Eminem raps: "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."
Chris Brown was charged with assaulting Rihanna in 2009.
The song comes on his new album Music to be Murdered By Side B, which accompanies
an album he released in January of this year.
At the time the track leaked last year, Eminem's spokesperson said: "This is a leak of something that's over 10 years old. After Eminem recorded it, he scrapped it, and rewrote it."
Since 2010, Eminem and Rihanna have collaborated on a number of occasions, including on songs 'Love the Way You Lie', 'Numb' and 'Monster'.
