Floyd Mayweather has refused to rule out a potential super fight with UFC star Conor McGregor, insisting that there is no deadline for the fight to occur.

Mayweather retired from boxing in September 2015 but has become embroiled in a war of words with McGregor on social media - and has previously said he would make a return to the ring for a cross-over bout with the Irishman. This week he has stepped up his interest in the fight and urged the UFC lightweight champion to make a decision.

The situation is complicated by McGregor’s UFC contract, as they would have to agree to any potential fight between the pair. The Irishman is also currently taking a break from the sport as his girlfriend Dee Devlin is due to have a baby boy in May.

When asked by Sky Sports if there was a deadline for a bout with McGregor, Mayweather said: “We have to take it one day at a time.

"Can the fight with Conor McGregor happen? Absolutely - it is possible. We just don't know at this particular time. We will have to wait and see what the future holds.

"One thing that we do know about Conor McGregor - when he stands up he goes out there and kicks a**. When he is on the ground that is something totally different.

"I have been off since 2015 so I could be rusty, I just don't know. We don't know what the future holds or if he wants to fight. We will have to see."

UFC president Dana White, who will also have a big say in whether the fight happens, was asked about the fight last week and told TMZ: “We’re nowhere near it”.

Interestingly, White also stated that he expected McGregor’s next fight to be a UFC encounter against the winner of an interim lightweight title fight between Khabib Nurmagomedov and Tony Ferguson.

The fight scheduled for UFC 209 last Saturday never occurred, though, after Nurmagomedov was hospitalised due to difficulties making the 155lb weight limit. Michael Johnson was drafted in as a replacement but Ferguson declined the bout, as his pay was reduced and it would not have been for an interim title. 

This has added more speculation over McGregor’s next opponent, with Nate Diaz also mentioned as a possible opponent in a UFC bout.

Mayweather’s last fight was against Andre Berto in September 2015 after which he retired, having matched Rocky Marciano’s record of 49 fights unbeaten.