Kickboxing veteran Liam Harrison has denied that he's facing five division champion Floyd Mayweather in an exhibition fight on February 25 at The O2 in London.

Mayweather, who turns 46-years-old next month, recently announced that he would be facing Harrison in the main event of that card - and even circulated the official poster for the event on social media.

"London February 25th, It’s official. My first exhibition fight in the UK will be at the O2 Arena. Tickets go on sale next week. Stay Tuned," Mayweather stated.

However, Harrison - who is contracted to ONE Championship - denied the information - explaining that he's still recovering from an injury and wouldn't be ready in time.

"Many of you will have seen the announcement this morning about my fight with Floyd Mayweather. Devastatingly, my knee just won't allow it. Discussions about the fight started a few days ago with the Mayweather team and I honestly thought I would be ok in a boxing fight, even needing surgery on my knee," Harrison explained.

"I upped my training as soon as discussions started and had some hard sparring and pads but almost immediately my knee had ballooned up and I can't walk. Hitting pads is fine but the movement and agility needed to spar and especially fight just isn't possible.

"My surgeon is in agreement that this won't be possible and I am absolutely heartbroken. This fight and everything that would have come with it would have changed my life. Furthermore, no contract for this has been received or signed. I'm exclusively contracted to ONE and I had approached them for permission and sign off.

"Without receipt of the contract and ONE's review and approval of this, nothing was confirmed. Floyd is the greatest boxer of all time and I would have wanted to put in a good account of myself. Not just for me but for the whole muaythai community... I'm seriously flattered to have been even approached for this fight and I really think I could have done well in it. But, as things stand, I'm going to have to stick to my surgery next week. I really hope when I'm recovered we can make this fight happen."

Harrison has a career record of 90-25-2, with 50 knockouts.

Mayweather retired from the sport in 2017, but he's entered the ring several times in exhibition fights.