(CNN) - Justin Bieber wants to fight Tom Cruise... and no one knows why.
The 25-year-old singer tweeted the challenge to the 56-year-old actor on Sunday appearing to jokingly taunt Cruise.
He even tagged Dana White, head of the ultimate fighting championship, asking if he'll host the match.
Former UFC champ Conor McGregor says he's totally for it and offered to host if cruise accepts the challenge.
It's unclear why Bieber wants to take on Cruise.
Neither of their reps have commented yet.
I wanna challenge Tom Cruise to fight in the octagon. Tom if you dont take this fight your scared and you will never live it down. Who is willing to put on the fight? @danawhite ?— Justin Bieber (@justinbieber) June 10, 2019
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