Conor McGregor out of UFC 200 after dispute over press conference

Conor McGregor is officially out of UFC 200, UFC president Dana White announced Tuesday after the fighter tweeted earlier in the day that he's retiring from the sport.

White said he pulled McGregor from his scheduled rematch with Nate Diaz due to the Irish fighter's unwillingness to attend a Las Vegas press conference this week.

"Conor didn't want to come to Las Vegas and be part of any promotional training," White said on ESPN's SportsCenter. "He's in Iceland ... 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."

White didn't confirm or deny McGregor's retirement.

"Is Conor McGregor retiring? Only he can answer that question. I don't know," White said. "But he will not be a part of UFC 200."

White added, "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."

As for Diaz, he'll meet with UFC officials this week after he arrives in Las Vegas on Tuesday evening to discuss a new opponent for him to face at the July 9 event. The super card could see a major shake-up depending how the UFC decides to proceed with the Diaz fight.