Dual middleweight world boxing champion Daniel Geale says his upcoming rematch with Anthony Mundine could be his last fight in Australia for a while.

Mundine, who handed Geale his only professional loss in 2009, tweeted on Tuesday: "Geale wanted it now he bouts to get it! And the NEW unified middleweight champion of the world!!

It is expected the bout will take place in January, with the date and venue expected to be confirmed at a Sydney press conference on Thursday.

"I'm really excited about it," WBA Super and IBF title holder Geale told AAP.

He lost his IBO middleweight title to Mundine on a split points decision in Brisbane in May 2009, but Mundine declined to give him a rematch.

Mundine is the ninth ranked IBF contender, but isn't currently rated in the WBA top 15.

American promoter Gary Shaw has secured an "Exception to Regulations" by the IBF for Geale to participate in an optional IBF defence rather than a scheduled mandatory.

Geale 31 (28-1, 15 KOs) thought the fight could still be for both belts.

"This is probably the last opportunity (for a while) to have a fight in Australia," Geale said.

"I think I've got some big things that I need to do in other countries as well.

"In the US there's a fair bit of interest."

Geale said he would enter the Mundine fight very confident because "The Man" had been keeping his distance for a while.

"He does talk a lot of trash, but he knows I've improved every fight that I've had since we fought," Geale said.

"He knows that the next fight is going to be so much different and so much harder.

"I think he's just trying to get into my head as much as he can, but it's not going to work and he will definitely pay when the time comes."

Mundine, 37, (44-4, 26 KOs), who previously held the WBA super middleweight title, has won 21 of his last 22 fights.

"People are saying he (Geale) is the best middleweight in the world, but he is not even the best middleweight in Australia," Mundine said.

"I beat him once and I'll do it again."