Mayweather and McGregor were offered $25 million each plus pay per view points from UFC President Dana White.
The idea of a meeting between retired boxer Mayweather, who never lost a professional fight, and Irish UFC star McGregor has circulated amongst the fight community since the latter was granted a professional boxing licence in California previous year.
"It makes complete sense for Conor McGregor to want to go fight Floyd Mayweather because Floyd doesn't really knock anybody out". My number was a guaranteed $100m.
Mayweather is technically retired with a record of 49 fights unbeaten and now spends most of his time promoting bouts like tonight's unification clash between James DeGale and Badou Jack.
Prior to McGregor's first bout with Nate Diaz last March, many questioned the jiu-jitsu skills of the Irish star.
Payet's West Ham tantrum just like Torres at Liverpool - Carragher
If we gain confidence, if we gain team character from this then it would help us to be a better team and that's what we aim to do. West Ham have rejected a £20m bid from Payet's former club Marseille, with the 29-year-old keen on a return to his homeland.
While McGregor's disclosed paydays for his last several fights have been short of that number, he is believed to make well above $10 million per fight when pay-per-view bonuses are included.
During an interview on ESPN's First Take Mayweather said, "They know what my number is". As for his chances in a boxing match with Floyd Mayweather Jr., well.McGregor would have to be considered a big underdog there if the fight were to happen before Mayweather turns 45.
If you think money-eyed promoters wouldn't bite, think again. It's not true. I made an offer. He never made an offer. "There's a reason you want this Conor McGregor fight so bad, because you know that's your money fight".
Another issue White has with Mayweather is his self-perception. "I think it's a very smart fight for both guys", he said.
However, Mayweather also made it clear that he would be the significant favorite in terms of fighter pay, asking to compare what he's made in the past to what McGregor has made in the past and set the purses accordingly.