Justin Bieber is weighing in on Eminem’s recent work.

The pop superstar took to Instagram Stories, posting a screenshot of himself listening to Eminem’s Kamikaze track “The Ringer.” While he admitted to liking his flow, Bieber called out the Detroit rapper for “dissing” younger MCs and claimed he doesn’t understand the new wave of hip-hop.

“I just like Em’s flow but don’t like that he’s dissing new rappers,” wrote Bieber. “I like the new generation of rap he just doesn’t understand it.”

On “The Ringer,” Em calls out Lil Yachty (“I can see why people like Lil Yachty, but not me though / Not even dissin’, it just ain’t for me”) and mumble rap (“I heard your mumblin’ but it’s jumbled in mumbo jumbo / The era that I’m from will pummel you, that’s what it’s comin’ to”), while praising MCs like J. Cole, Big Sean, and Kendrick Lamar.

Bieber himself has been the subject of criticism. He recently lashed out at an E! News host who criticized him for lip-syncing during his surprise performance with Ariana Grande at Coachella. While on stage, he revealed that a new album was “coming soon.”

He recently teased new music on social media, posting the number “10” alongside side-by-side photos of him and Ed Sheeran. The singers have reportedly teamed up for a new collaboration, which could drop on May 10.