The UFC is in chaos.

After its biggest star - Irish sensation Conor McGregor - shocked the world with a surprise retirement announcement, UFC boss Dana White has reacted by pulling him from the biggest card of the year.

The sensational turn of events began Wednesday morning when McGregor tweeted the following: "I have decided to retire young," the UFC superstar tweeted. "Thanks for the cheese. Catch ya's later."

The landscape-changing declaration was initially met with skepticism. But after hours of silence, the UFC has revealed the dispute behind the Irish fighter's shock move.


White announced McGregor is being pulled from UFC 200 - the mega-event in July where he was scheduled to fight a rematch against Nate Diaz - because he refused to attend a press conference in Las Vegas this week to promote it.

"Conor didn't want to come to Las Vegas and be part of any promotional (work)," White said. "He felt leaving right now would hurt his training. But every other fighter on the card is coming. It doesn't make you exempt. We spend a lot of money on this stuff ...

"Obviously we still have a good relationship with Conor. I respect Conor as a fighter and I like him as a person. But you can't decide not to show up to these things. You have to do it."

White said McGregor didn't want to attend the press conference because he didn't want to interrupt his training for UFC 200, which saw him travel to Iceland this week.

"Conor did not want to come to Las Vegas and film the commercial or be a part of any of the marketing we have," White said. "He's in Iceland training and that's not possible."

Back in the land of Ice for some good training at Mjolnir!! #TheIceViking

Posted by Conor McGregor on Monday, 18 April 2016

The revelation sheds light on the Irish superstar's surprise tweet. McGregor (19-3 MMA, 7-1 UFC) is the biggest star in the sport, just 27 years old and was set to make millions at UFC 200. So naturally his retirement came out of the blue.

There was a perception McGregor was sending a message to the UFC hierarchy - and that's now been confirmed.

Whether he follows through on his retirement threat remains to be seen. "Is Conor McGregor retiring? Only he can answer that question," White said. "I don't know, but he's not fighting at UFC 200."

McGregor's coach, John Kavanagh, appears to be on board with the decision, tweeting: "Well was fun while it lasted."

Kavanagh, who runs the Straight Blast Gym in Ireland which has produced several UFC fighters, later added on Facebook: "Mate of mine did his first year apprenticeship in plumbing a few years back. Looking to start up again if anyone can help." He also tweeted a link to the Eminem song "Without Me".

McGregor's removal severely hinders the UFC's ability to deliver the blockbuster event it had promised at UFC 200.

The card had already been met with some indifference and being forced to change the main event at short notice is a headache White didn't need.

Diaz - who stands to lose the most in the short-term from McGregor's stand-off with the company - tweeted, "I guess my work here is done. I'm retiring too" in response to McGregor's tweet.

It was clearly in jest, but the UFC now has to decide whether Diaz became a big enough star in his first fight against McGregor to stay as a headliner for UFC 200.

The fight between Jose Aldo and Frankie Edgar will also be impacted. If McGregor is indeed retiring - is the featherweight belt now on the line?

It's not the first time the UFC has been in this situation. Diaz's older brother, Nick, was pulled from a tightly fight against Georges St Pierre in 2011 after skipping a press conference.

He was later re-added to the card when St-Pierre pulled out with injury - so UFC fans will hold out hope McGregor and White can settle their differences and come together again.

Long-time UFC commentator Joe Rogan was in the middle of recording his podcast when the news of McGregor's retirement broke. His initial reaction was McGregor was trolling.

"He's decided to retire young ... which means like 34," Rogan said. "Listen man, unless he got f***ing head kicked today and knocked into oblivion, the idea he's going to go out on a loss like that to Nate Diaz ...

"Look he's got plenty of cash. If he wanted to retire young and step away - I guarantee you he probably made somewhere in the neighbourhood of $5 million for the Jose Aldo fight and probably made more than that for the Nate Diaz fight - I'd imagine after he spent a f***load of it, he's still got a few million bucks laying around.

"He's a hero in Ireland. He could always make money, run a gym and be fine. But this doesn't make any sense."