Conor McGregor and Dana White
White has been at the centre of McGregor's UFC rise. Getty

Dana White insists UFC will not sit back and allow Conor McGregor and Floyd Mayweather Jnr to negotiate a fight without the MMA promotion's involvement.

Both McGregor and Mayweather have spent the best part of a year teasing the possibility of the cross-sport spectacle that would surely be the richest fight in combat sport history.

The Irish Sun, citing a source close to the Dubliner, now claims both fighters have agreed terms and "settled on respective fees". The report goes onto add an official fight announcement could even follow within the next two weeks.

The decision for McGregor to pull out of an upcoming Q&A session in Dublin has added further fuel to the fire.

Amid the mounting speculation however, White has been quick to remind people that McGregor, the UFC's first ever concurrent two-weight champion, remains under contract with the promotion and still has four more fights to be fulfilled as part of that deal.

And White insists allowing what could very well be the most lucrative fight in history to happen without UFC weighing in simply isn't an option.

White told the Daily Telegraph: "Anything is possible. With my experience over the last however many f*cking years, I never say never anymore. But I would say the odds of this happening are about the same as me being the back-up quarterback for Tom Brady at the Super Bowl.

"He's [McGregor] under contract with me. How would I let somebody take this guy that I built and do it without me? That would be the stupidest move in history."

He added: "There is not a lot I wouldn't let Conor do. Conor is a very special individual. He has created a lot of opportunities for himself. The one thing I don't ever do is hold people back from opportunities."

While the Mayweather camp not too long ago described McGregor's efforts to push for the fight as a "con job" to "keep his name alive", the undefeated American now insists taking on the UFC superstar is the only fight that could possibly tempt him out of retirement.

"Most likely the fight between me and Conor McGregor will happen," Mayweather told Sky Sports while in attendance at the WBA welterweight title match between Carl Frampton and Leo Santa Cruz in January.

"That's the only fight that will get me back in the ring. He's going to do a job on his side and we are going to do a job on my side and hopefully all the fans in the UK come over and support me.

"I don't know [when it will be], I need to communicate with my team, the fight hasn't been made yet, but it is all about entertainment so hopefully we can make it happen."