Floyd Mayweather says he'll be back in December to fight Manny Pacquiao in a rematch of their 2015 superfight. (1:27)

Floyd Mayweather Jr. says a rematch of his much-hyped 2015 fight with Manny Pacquiao will take place this year.

Mayweather posted on Instagram Saturday, saying, "I'm coming back to fight Manny Pacquiao this year another 9 figure pay day on the way."

Mayweather made about $220 million from his May 2015 fight with Pacquiao and at the time posted a photo of a $100 million check -- his guaranteed purse from the bout.

Saturday's Instagram posting includes a video of Mayweather and Pacquiao talking to each other at a music festival in Tokyo, although it is difficult to hear what the men are saying.

In another angle of the interaction, Pacquiao tells Mayweather, "I have the belt," to which Mayweather responds, "I'm going to take it from you like I did before."

Mayweather included no details about the potential matchup in the post, but in videos obtained by ESPN from a Pacquiao adviser, Mayweather says he is targeting December for a comeback.

"We gonna take the belt. We gonna get the payday. And I don't want no shoulder excuses," Mayweather said.

Mayweather (50-0, 27 KOs) earned a unanimous decision win over Pacquiao in their first fight. Pacquiao said he was hampered by a right shoulder injury while landing only 81 punches in that bout. The massively hyped fight delivered a record 4.6 million pay-per-view buys but was largely panned by most boxing fans.

The 41-year-old Mayweather has two wins since facing Pacquiao: against Andre Berto in 2015 and his August 2017 knockout of Conor McGregor in the UFC star's boxing debut. Mayweather said after the McGregor bout that "this was my last fight."

Pacquiao (60-7-2), 39, last fought in July, defeating Lucas Matthysse to win a secondary welterweight title. The Filipino fighter called out Mayweather after the win.

There are no promotional barriers between the two men, because Mayweather promotes himself and Pacquiao is a boxing free agent.

The Westgate Las Vegas SuperBook has posted odds on the potential matchup, with Mayweather listed as a minus-220 favorite and Pacquiao at plus-180. The fight must take place by Dec. 31, 2019, for these bets to count.

The Associated Press contributed to this report.