The mega-fight between Conor McGregor and Floyd Mayweather is inching closer to reality.

The Irish Sun reports the Ultimate Fighting Championship lightweight champion and the five-division world boxing champion have agreed to financial terms for a bout.

A deal has not been formally signed, though, because of "a third-party hold up," presumed to be from the UFC.

Though McGregor doesn't have any fights scheduled on the docket, UFC president Dana White revealed last week that he has four fights remaining on his current contract. Because of the uncertainty surrounding the McGregor situation, the UFC 209 bout between Tony Ferguson and Khabib Nurmagomedov is now scheduled for interim lightweight title.

The report says that McGregor, 28, will be travelling to Las Vegas this week to film an anti-bullying public service announcement as part of a deal struck with the Nevada Sport Commission after attempting to hit Nate Diaz with a water bottle at a press conference ahead of UFC 196 last march. The Dublin native was originally given a $150,000 fine for the incident.

Mayweather, 39, has not fought since a September 2015 unanimous decision victory over Andre Berto. After that fight, he declared that he was retired, finishing his career with a 49-0 record.