Floyd Mayweather and Justin Bieber are at loggerheads ahead of this weekend’s fight for Mayweather with Irishman Conor McGregor.

The beef appears to have started over some sort of dropping of Mayweather as a friend by Justin Bieber after the recording artist unfollowed Mayweather on Instagram.

As petty as that sounds.

TMZ have reported that Mayweather has labelled Bieber:

“A traitor.”

They’ve also mentioned that Mayweather told Bieber:

“You’re dead to me.”

Strong words there, Floyd.

They’re report below also goes on to say that Mayweather was absolutely furious.

Justin Bieber and Mayweather understood to be good friends in the past. Bieber had accompanied the American fighter on the way to the ring before some of his bouts.

Mayweather has had some very public falling outs in the past with some of his celebrity friends.

The other most notable example was with rapper 50 Cent after an apparent falling out to do with a boxing promotional venture that the rapper was involved in.

It is not known yet who will walk Mayweather out to the ring this weekend against McGregor – but the leading tip thus far for his entrance song and walk out has been rap artist Little Wayne.

For the full report on Mayweather and Justin Bieber’s beef check it out here on the TMZ YouTube channel (hat tip):