Ouch! Mariah Carey says she doesn't know Demi Lovato or Ariana Grande

Apparently Mariah Carey isn’t up on her pop icons – or admitting to it anyway.

A guest on Andy Cohen’s “Watch What Happens” Sunday, Carey threw diva-level shade at Ariana Grande and Demi Lovato while playing the game “Plead the Fifth.”

Carey deftly dodged questions during the game about her recent breakup with James Packer and her rumored romance with backup dancer Bryan Tanaka, but when queried about Lovato and Grande, the Grammy-award winning singer got real.

Several months ago Lovato went off via social media on the star of “Mariah’s World" about her treatment of Jennifer Lopez, Carey famously denied knowing the singer.

“I don't know her either and so I wouldn't say anything to her," she said about Lovato, 24. "She should come up, introduce herself to me, say, 'Here's my opinion, what do you think about it?' That's how you handle s--t, OK?"

Carey also spoke about Grande during Sunday's show. Two years ago Carey dismissed a comparison between herself and Ariana Grande during a radio interview on Power 105.1.

When Cohen asks Carey pointedly whether or not she knows the 23-year-old Nickelodeon star, Carey flatly says, “No.” "…I don't know... Honestly, I'm not familiar. I listen to hip-hop more than I listen to pop music.”