Former boxing world champion Floyd Mayweather has refused to bid for more than $ 1.3 billion, mocking previous challengers Canillo Alvarez and Ireland's Connor McGregor to face him again after defeating them earlier.

The 42-year-old said he did not need to face up again for big sums, and boasted that he already had a huge fortune of more than $ 1 billion.

This was in response to boxer promoter Oscar de Lahoya trying to tempt Mayweather to another match against Canillo Alvarez, saying the confrontation would cost more than $ 1.3 billion, as did McGregor's repeated requests to face him again through social networking sites.

"They are not the only ones who want a second chance to face him. There are others," he said. "No one can defeat him.

Mayweather retired unbeaten after winning McGregor in his final 50th game in August 2017. The US boxer also beat Canillo Alvarez in 2013.

Mayweather played an easy-to-watch match after retiring for $ 9 million, winning less than two minutes after Japanese boxing champion Tenzin Nasukawa on the last night of last year.