Floyd Mayweather claims he can’t pay off his 2015 tax liability until after he wins money from his upcoming fight against Conor McGregor.

Floyd Mayweather Conor McGregor fight

The 40-year-old retired boxer filed a petition to the IRS on July 5 asking for a reprieve until the bout, which is set for Aug. 26 at Las Vegas’s T-Mobile Arena. The petition asks the government to reduce Mayweather’s penalty on the unpaid taxes.The failure-to-pay penalty is typically 0.5 percent of the owed taxes for each month, according to the IRS website. Mayweather is 15 months behind on his tax payments. Therefore, the boxer would be paying a 7.5 percent penalty. 

“Although the taxpayer has substantial assets, those assets are restricted and primarily illiquid,” the petition said, according to the legal website Law360. “The taxpayer has a significant liquidity event scheduled in about 60 days from which he intends to pay the balance of the 2015 tax liability due and outstanding.”

It remains unknown exactly how much money Mayweather owes, although the IRS had previously purported that the former boxer had the resources to pay it immediately, even if it meant selling property or taking out a loan.

Mayweather earned $220 million from his fight with Manny Pacquiao on May 2, 2015. On Monday, Mayweather shared on Instagram a picture of a $100 million check — his guaranteed purse from the match — that did not have taxes deducted from it. Sources confirmed at the time that the check was real.

The boxer is predicted to win a similar amount from his fight against McGregor.

In the aforementioned Instagram post, Mayweather revealed that he payed $26 million in taxes in 2015 and asked, “What else could they possibly want.”

Mayweather has earned approximately $700 million in his 49-fight professional career, according to a Forbes magazine estimate.

Forbes also estimated Mayweather’s net worth as of January to be around $340 million.

Caption:LAS VEGAS, NV – SEPTEMBER 12: Andre Berto (L) and Floyd Mayweather Jr. battle in the 11th round of their WBC/WBA welterweight title fight at MGM Grand Garden Arena on September 12, 2015 in Las Vegas, Nevada. Mayweather retained his titles with a unanimous-decision victory. (Photo by Ethan Miller/Getty Images)

Conor McGregor took one step closer to securing his boxing match against Floyd Mayweather on Wednesday by signing a contract to fight the retired legend.

Conor McGregor signs deal for Bout vs Floyd Mayweather

“The first, and most important part of this historic contract has now officially been signed off on,” McGregor said in a statement to Themaclife.com. “Congratulations to all parties involved. We now await [Mayweather’s adviser] Al Haymon and his boxer’s signature in the coming days.”

The 28-year-old Irish UFC star also said: “It is an honor to sign this record-breaking deal alongside my partners Zuffa LLC, The Ultimate Fighting Championship and Paradigm Sports Management.”

McGregor did not disclose the terms of the contract, though early on Tuesday he tweeted a photo of himself and his baby boy sitting on a couch next to his championship belt.

The Irishman’s signing of the deal was confirmed just hours after UFC president Dana White told TNT’s NBA crew that McGregor had agreed to the long-awaited fight, and that they were now simply waiting fro Mayweather’s side to sign the agreement.

“The McGregor side is done,” White said Wednesday night while appearing as a guest on the network’s post-game wrap-up of Game 1 of the Eastern Conference finals, in which the Cleveland Cavaliers defeated the Boston Celtics 117-104 at TD Garden. “I’m starting to work on the Mayweather side now.”

The UFC president continued, clarifying that the bout was not yet a certainty: “I’m not saying the fight will happen, but I’ve got one side done,” White said. “Now it’s time to work on the other. If we can come to a deal with Haymon and Mayweather, the fight’s gonna happen.”

White added the highly-anticipated bout would only be a boxing match, and not include any sort of mixed martial arts fighting.

Mayweather stated on Wednesday that he was awaiting details from McGregor and White.

“I’m not here to throw anybody under the bus, [and] I can’t sit here and say that they are waiting on us,” the undefeated boxer said in London. “I’m not saying that. And we’re not waiting on them.

“I have a team for [negotiating], but as soon as their side [UFC] communicates with our side, then the fight will happen.”

Since McGregor is under contract with the UFC, he cannot agree to a deal with Mayweather independently.

The Irishman is 21-3 in mixed martial arts and remains the only fighter in UFC history to own two belts simultaneously, an accomplishment he reached by defeating lightweight champion Eddie Alvarez at Madison Square Garden in November.

White also said McGregor wishes to fight twice this year.

“He wants to fight twice this year and one of those fights to be Floyd, if possible,” White told ESPN.

Mayweather, meanwhile, retired from boxing in September 2015 after finishing with an impressive 49-0 record. The 40-year-old has beaten nearly every fighter near his weight class: Manny Pacquiao; Saúl Álvarez, (aka Canelo); Miguel Cotto; Juan Manuel Marquez; Oscar De La Hoya, and dozens more.

The legend said McGregor is the only one he is interested in right now, primarily because it makes the most financial sense.

“There’s only one fight that makes business sense,” Mayweather said. “I came out of retirement because I’m a businessman and I want to give the world what they want to see.

“McGregor’s a fighter. I’m a fighter. This is what the fight fans and MMA fans want to see.”

LAS VEGAS, NV – DECEMBER 12: Conor McGregor celebrates after a first-round knockout victory over Jose Aldo in their featherweight title fight during UFC 194 on December 12, 2015 in Las Vegas, Nevada. (Photo by Steve Marcus/Getty Images)

UFC president Dana White is determined to accelerate negotiations for a potential boxing match between Conor McGregor and Floyd Mayweather, and has set a deadline to conclude discussions with one of the two camps.

Dana White Sets Deadline for Conor McGregor Talks about Floyd Mayweather Fight

White says he hopes to wrap up talks with McGregor about the fight on Sunday so that he may then begin speaking to Mayweather’s team.

“I plan on having this thing locked up by this Sunday and then moving on to Team Mayweather and starting a negotiation with them,” White announced Thursday on Jim Rome’s radio show. “If we really do get it done in that time frame, then this thing could possibly happen.

“But again, I still need to go negotiate with [Mayweather’s team]. There’s no guarantee that we’re going to come to a deal.”

The 47-year-old UFC president, who has been in charge of the organization since 2001, added he plans to start discussions with Mayweather’s crew on Monday. White added he feels “pretty good” about reaching an agreement with the undefeated boxing champion.

White stated in April that he was in favor of the McGregor-Mayweather bout, which the Irish UFC fighter first expressed interest in, even going as far as to obtain his boxing license in the state of California in order to prepare to battle the 40-year-old Mayweather, who retired in 2015. The UFC president also expressed his support for the bout in an interview on “Conan” last month.

According to White, McGregor could win approximately $75 for defeating the legendary boxer. This would reduce the Irishman’s earnings from the UFC, where he is a lightweight champion.

McGregor previously suggested to fight Mayweather for up to $100 million.

The UFC president admitted, however, that he is not entirely confident Mayweather will go through with the deal for a fight.

“The Conor side — we’re good on the Conor side,” White said last month. “I need to figure out the Mayweather side, and maybe it can’t be. Maybe the Mayweather side can’t be done. We’ll see. I promised Conor I’d do everything I could to make this fight happen, so that’s what I’m going to do.”

White also said he wants to quicken the pace of these negotiations so that he may continue dealing with other matters in the UFC.

“Yeah I just can’t keep messing with this thing,” he said. “I need to run my business and I have to focus on all the other things that are going on around here.”

NEW YORK, NY – APRIL 27: UFC president Dana White appears during a media availability for UFC 200 at Madison Square Garden on April 27, 2016 in New York City. (Photo by Jeff Zelevansky/Getty Images)