ARLINGTON, TEXAS - MARCH 16: Floyd Mayweather Jr. stands in the ring before Errol Spence Jr takes on Mikey Garcia in an IBF World Welterweight Championship bout at AT&T Stadium on March 16, 2019 in Arlington, Texas.

Mayweather 'coming out of retirement,' working on event with Dana White

Tom Pennington / Getty Images Sport / Getty

Floyd Mayweather appears set to return to the ring, or perhaps the Octagon.

The undefeated boxer, who told Rory Carroll of Reuters earlier this month that he was finished with the "brutal sport" of boxing, announced Thursday that he will come out of retirement in 2020.

Mayweather said in another Instagram post Thursday that he and UFC president Dana White are working together on an event.

View this post on Instagram

@danawhite and I working together again to bring the world another spectacular event in 2020. #boxing #UFC #mma #mayweatherpromotions

A post shared by Floyd Mayweather (@floydmayweather) on Nov 21, 2019 at 7:24pm PST

This wouldn't be the first time Mayweather crossed paths with the mixed martial arts promotion. He fought former UFC two-division champion Conor McGregor in 2017, and both fighters earned lucrative paychecks.

White reposted Mayweather's announcement on his Twitter but has yet to disclose specific plans for the apparent 2020 event.