Justin Bieber backtracked when asked last week if he was serious about taking on Tom Cruise in the Octagon, joking that the 56-year-old Mission Impossible star would "whoop my ass in a fight".

TMZ claims pop star Justin Bieber has agreed to a face off against Top Gun star Tom Cruise in an unbelievable UFC showdown in the Octagon.

They report that Ari Emanuel, the co-CEO of the William Morris Endeavor agency owning UFC, had a conference call with Bieber's manager and UFC President Dana White.

Bieber’s manager Scooter Braun is reported to have intimated the celebrity would "absolutely" fight Cruise, if the Mission Impossible icon was up for it too.

Justin Bieber is ready to rumble with Tom Cruise. Despite reports that the Bieb was only joking about wanting to fight Cruise, Bieber's agent and manager have spoken to UFC about getting the two stars into the Octagon. pic.twitter.com/A56rWgBvkd — The Morning X w/ Mark & Chris (@89XMorningX) June 21, 2019

​It was claimed that Emanuel "strongly believes" Cruise, 56 and in incredible shape, would agree to step into the Octagon.

What seems to have started as a joke challenge idly tossed out on Twitter, might actually happen, if the reports circling in the media are true.

Canadian Justin Bieber, a huge international pop icon estimated to have sold around 140 million records, started talk of a fight with Tom Cruise in a tweet posted last week, as he tagged UFC boss Dana White in the message:

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

The tweeted challenge set off a frenzy on social media.

Dude, I'd actually pay to see Tom Cruise beat the crap out of Justin Bieber. Make it happen. — NotGayCeeJay (@TheBigCeeJay) June 21, 2019

​However, when the challenge was followed up by TMZ last week, Bieber responded with a clarification:

“Man... I was just playing, it was just a random tweet, I’m pretty sure Tom would probably whoop my ass in a fight,” he said.

“I’d have to get super in shape, I’m really skinny right now. I think he’d probably be out of my weight class. He’s got that dad strength.”

A bubbly Justin Bieber explaining the story behind his tweet for Tom Cruise is pure gold pic.twitter.com/JwZwwpqRm7 — ˚*❋ fαn α¢¢ (@Groovybiebz) June 16, 2019

​Dana White, speaking about the possible bout, is cited by TMZ as saying:

“Let me tell you what, I’d be an idiot not to make this fight. That would be the easiest fight to ever promote in the history of my career.”

Enter the octagon: Justin Bieber’s fight with Tom Cruise could actually happen https://t.co/qqQLVxNNRh pic.twitter.com/nEtasjfioj — NME (@NME) June 21, 2019

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Damn Tom this didn’t go as planned https://t.co/C2cXfVHZyM — Justin Bieber (@justinbieber) June 10, 2019

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