Floyd Mayweather claims he is 'officially' coming out of retirement to fight Conor McGregor, urging the MMA star to sign terms with his UFC bosses so they can meet this summer.
The five-weight world champion is ready to return in a cross-codes bout against the Irishman, himself a record-breaking two-title champion with the UFC, this June but says his opponent's lust for money is threatening to derail talks.
Speaking in Liverpool's Auditorium on the latest leg of his UK Undefeated Tour, Mayweather said McGregor must accept his 'B-side' status in the fight and gave examples of when he himself accepted the same role in order to prove himself.
The 40-year-old said: 'When I faced Arturo Gatti, I went to his turf and he was the A-side I was the B-side,' said Mayweather. 'I beat him and I didn't cry or I didn't complain.
'Oscar De La Hoya, he was the A-side, I was the B-side. I didn't cry, I didn't complain. I beat him and I became the A-side.
'Now Conor McGregor, I'm officially coming out of retirement just to fight Conor McGregor. I don't wanna hear any more excuses about the money.
'Sign the paperwork with the UFC so you can fight me in June, simple and plain. Let's fight in June. You're the B-Side, I'm the A-side.
'I'm tired of all this crying about money and blowing smoke up everybody's a**. If you want to fight, sign the paperwork and let's do it.'
Mayweather has not stepped inside the ring since beating Andre Berto by unanimous decision in September 2015, equalling Rocky Marciano's 49-0 record in the process.
But despite any ring rust that may have gathered, he would go into any boxing match with McGregor as the heavy favourite with critics unsure whether he would be able to adapt from his current discipline.
Indeed, footage of him sparring released last year failed to inspire confidence, but McGregor has been quoted as saying his next professional fight will be in a square ring rather than an octagon.
A June fight is made all the less likely by the fact that McGregor is currently taking a break from all forms of sport because of the impending arrival of his first child with partner Dee Devlin.