Featherweight champion McGregor had stunned the mixed martial arts world last week by announcing his “retirement” before later backtracking.
The UFC responded by removing the 27-year-old from the billing for his July 9 fight with Diaz on the UFC 200 card in Las Vegas.
However McGregor insisted in a tweet on Monday that he was back on the card and looking forward to fighting.
But in an interview with the TMZ sports website, White said he was baffled by McGregor’s announcement.
“It’s not true. We haven’t talked to Conor or his manager since the press conference. I don’t know why he would tweet that,” he said.
White added: “All the media keeps asking me that. I feel like the scene in ‘Step Brothers’ when they ask if they can build the bunk beds. I don’t know how many more times I can say the fight is off or how many more press conferences I can have saying the fight is off for people to believe it’s off.”
