The entries were found among photographs and handwritten lyrics inside the singer's Minnesota home following his death in 2016 at the age of 57.
According to The Guardian's Weekend Magazine, the "Purple Rain" hitmaker revealed his feelings about the pop stars as he criticized the music industry as he wrote, "We need to tell them that they keep trying to ram Katy Perry and Ed Sheeran down our throats and we don't like it no matter how many times they play it."
The outlet reported Prince's estate was going through his belongings to generate income, including compiling his letters for a new book titled "The Beautiful Ones," which was overseen by a die-hard Prince fan, Dan Piepenbring, whom the late singer had tapped to work on his memoirs before his tragic death.
Prince died in his home from an accidental drug overdose in April of 2016.
"The sheer quantity of paper was surprising. There was no real method to the madness. In one room you'd find something from 1979, and within arm's reach there'd be something from 2002," Piepenbring told the publication.