Cardi B, 26, returned to Instagram Wednesday to announce the new collaboration with Mars, 33.
Cardi B posted cover art for the new single, but did not share the song's title. The image shows the singer wearing a studded purple and black leather ensemble with fishnet stockings, while Mars sports a teal shirt and pinstriped pants.
"Ok so I'm back from retirement to announce I have a brand new song coming out Friday at midnight with @brunomars #twogrammywinningartist," Cardi B wrote.
Mars, who previously collaborated with Cardi B on a remix of his single "Finesse," posted the same photo on his own account.
"NEW SONG THIS FRIDAY!" the singer wrote.
The news comes just two days after Cardi B deactivated her Instagram account. The rapper deleted her profile following criticism of her win for Best Rap Album for Invasion of Privacy at the Grammy Awards on Sunday.
"I remember last year when I didn't win for Bodak Yellow and everybody was like, 'Cardi got snubbed,'" she responded in a since-deleted video Monday. "Now this year's a [expletive] problem?"