Rock legend didn't like it when Yeezy declared himself "the greatest living rock star on the planet".

Rock legend David Crosby has revealed why Kanye West “bugs” him.

Crosby – a founding member of both the Byrds and Crosby, Stills & Nash – said he objects to the rapper’s infamous brag at Glastonbury Festival in 2015.

“I’m the greatest living rock star on the planet,” West told the crowd while performing on the Pyramid Stage.

Discussing his issues with the rapper on Andy Cohen’s US chat show Watch What Happens Live, Crosby said: “He can neither sing, nor write, nor play.”

“The thing that bugs me about him is the ‘I’m the greatest living rock star’ [thing],” Crosby added. “Somebody needs to drive him over to Stevie Wonder’s house right now so he understands what a real one is. Secondly, they should send him all of Ray Charles’s catalogue so he can learn how to sing.”

Watch the clip of David Crosby discussing Kanye West below.

At the time of writing, West has yet to respond to Crosby’s comments. The rapper recently said he will not attend next year’s Grammy Awards if Frank Ocean’s album ‘Blonde’ isn’t nominated.

He has also appeared to hit out at former collaborator Jay Z in the wake of Kim Kardashian’s recent robbery in Paris.