Boxer Floyd Mayweather could be open to a bout with Khabib Nurmagomedov after responding to the UFC fighter's challenge by saying: "Get the chequebook out!"

On Sunday the 30-year-old Russian called out American Mayweather, who is also undefeated, adding: "In the jungle there is only one king."

Mayweather, 41, beat Conor McGregor in a boxing bout in August 2017.

The Irishman's return to UFC ended in defeat by Nurmagomedov on 6 October.

That extended Nurmagomedov's unbeaten mixed martial arts record to 27-0.

Former five-weight world champion Mayweather, who is unbeaten in 50 fights, said on Twitter: "CBS, Showtime and MGM Grand get the chequebook out!"

It came after Nurmagomedov, in an Instagram video filmed with Leonard Ellerbe, the chief executive of Mayweather Promotions, said: "Let's go, Floyd, we have to fight now,

"50-0 v 27-0 - two guys who never lose. Why not?"

 Khabib Nurmagomedov beat Conor McGregor at UFC 229

Nurmagomedov, renowned for his wrestling skills, caught McGregor with a punch before winning their contest with a choke as he forced his opponent to tap out.

Mayweather stopped McGregor in the 10th round in their fight, one of the richest bouts in boxing history.

"Of course I am the king because he could not drop McGregor and I dropped him easily," added Nurmagomedov, who retained his UFC lightweight title against McGregor.

Mayweather, who has not fought since the McGregor bout, has said he will come out of retirement to fight Manny Pacquiao in a rematch later this year.

Nurmagomedov and McGregor have both been temporarily suspended by the Nevada State Athletic Commission pending a full investigation into the scenes that marred the end of their fight in Las Vegas.

Following his victory, Nurmagomedov jumped the octagon fence and started fighting his rival's team. McGregor then fought with the Russian's camp as numerous brawls broke out.