Anthony Mundine apologised to boxing rival Daniel Geale on Sunday, admitting he overstepped the mark with offensive comments about his Aboriginal heritage.

Mundine said he instantly regretted the remarks which drew widespread condemnation, notably from within the Aboriginal community.

At a Thursday press conference to announce their highly-anticipated rematch, expected to take place in January, Mundine drew Geale's ire when he questioned the Tasmanian-born fighter's heritage - and said he didn't deserve to wear the Aboriginal flag on his boxing trunks.

But the barbs which hurt IBF and WBA middleweight world champion Geale most came when Mundine inferred he was less Aboriginal because he had "a white wife and white kids" - comments Geale said upset his wife, Sheena.

He now accepts those comments were out of line, with Geale accepting the apology.

"I think I went too far," said Mundine as he appeared alongside Geale on Channel Nine's Wide World of Sports on Sunday.

"I want to be man-to-man. I had a press conference, and I'll be man-to-man here and say I probably did (over)step the line about your woman and your children.

"I want to say I'm sorry, I'm sincerely sorry.

"After it came out I wanted to take it back but it was too late. I hope you accept my apology."

Mundine had already apologised on Friday to the Tasmanian Aboriginal community for saying he "thought they wiped all the Aborigines from Tasmania out."

During his Friday apology Mundine said he had a tendency to say the wrong thing before he realised it.

"Sometimes you say things and they're out of your mouth before you can even take it back," he said.

Geale was satisfied with Mundine's mea culpa and shook his hand - but said he still planned to let his boxing do his talking on the matter.

"It was something that did get me. Say whatever you want about me, I don't care but not the family, not the people I know," Geale said.

"I accept the apology. But when the time comes in the ring we'll sort it out.

"I do keep my opinions mostly to myself. Some of the things that he says I definitely don't agree with.

"Some things that he has said before I have agreed with, definitely.

"But the guy says some things that aren't right.

"That's him. That's what he does. I'm not like that.

"I'm a little bit quieter, I keep to myself a little bit more. I'd rather let my boxing do the talking."