Rapper 50 Cent has called out his former friend, heavyweight boxing champ Floyd Mayweather, suggesting he’s illiterate.

The Get Rich or Die Tryin’ rapper offered to donate $750,000 to a charity of Mayweather’s choice if he can read just one page of a book.

“Floyd will you except my ALS/ESL CHALLENGE. I will donate $750k to a charity of your choice, If you can read a full page out of a Harry Potter book out loud without starting and stopping or f–king up. Lmao,” he wrote as a caption to the video.

video via Instagram from 50 Cent

He then called Mayweather out again a few hours later, posting a photo of him in deep thought. “DAMN I CAN'T READ THAT WHOLE PAGE NOW. F--k you 50, Lmao,” he wrote.

image via Instagram from 50 Cent

HipHopDX reports the two have been feuding since 50’s friend Nelly started daying Mayweather’s ex-fiance. Mayweather also made comments about hip hop artists, which made the rapper mad, saying, "They come and go. But I'm still here."

Before posting the challenge, however, 50 posted a telling video about Mayweather gossiping about him, Nelly and rapper T.I. He ended it with his middle finger up.

“The computer say Floyd said 'F--k T.I. F--k Nelly. F--k 50. I'm like, 'What he say f--k me for?' Nelly f--ked your first baby momma Melissa, then took your f--kin' fiance. Say f--k that ni--a."

image via INFphoto.com