According to British newspaper The Sun, Stormzy told senior label bosses that he would quit Atlantic if Cook remained in his post.
“He stepped in and made it clear he would not be prepared to keep working with them if Ben stayed, and also that he might go public with the details of why,” The Sun quotes a source as saying.
The paper also alleges Stormzy banned Cook from standing at the side of the stage at his headline Glastonbury set in the summer.
Responding to the reports, a spokesperson for Warner Music Group tells Billboard, “That’s simply not true. No artists were involved in our decision-making.”
Cook joined the U.K. arm of Atlantic from British independent Ministry of Sound in 2007 and is credited with signing and developing the careers of Ed Sheeran and BRIT Award-winning dance act Rudimental, among others. He was promoted to president of Atlantic U.K. in 2014.
Following the news that he would be leaving the label, grime MC Wiley, who had previously worked with the exec, tweeted: "Ben Cook is not racist. Give that man back his job."
British rapper Kojey Radical also defended the label exec, tweeting, "Very dumb move, past or present. But he ain’t a racist."
Parlophone co-president Mark Mitchell has since assumed leadership of Atlantic on an interim basis.