According to multiple reports in Australia, eight division world champion Manny Pacquiao has pulled out of a planned November rematch with WBO champion Jeff Horn.

The fight was in the early planning stages, after Horn's win over Pacquiao in the "Battle of Brisbane" in July to take the WBO title.

Pacquiao is understood to have scheduling conflicts with the November 12 date, meaning Horn will have to find a challenger to defend his title.

Premier Annastacia Palaszczuk said the Government would still support Horn's WBO world welterweight title defence but against a new challenger, yet to be named.

"We have been advised today that Manny Pacquiao ... cannot return to the ring on 12 November as proposed," Ms Palaszczuk said. "I am advised Mr Pacquiao, who is also a Senator of the Philippines, will have other commitments at that time. Whoever the challenger is, my Government will help arrange the meeting because it will be good news for Queensland."

Duco Events, who promote Horn with Top Rank, issued a statement confirming that Pacquiao was out of the fight.

"Pacquiao is committed to fighting again in 2018 and a rematch with Jeff Horn for the WBO welterweight title. Until then, Top Rank, Duco Promotions, TEQ (Tourism and Events Queensland) and Brisbane Marketing will be exploring options," the statement said.

Horn (17-0-1, 11 KOs) pulled off a major upset when he secured a twelve round unanimous decision over Pacquiao in July at the Suncorp Stadium in Brisbane.

There was a rematch clause in the contract, which Pacquiao planned to exercise for the fall.

But a few days ago, Top Rank's CEO Bob Arum had already made statements that Pacquiao was potentially going to push back the rematch to 2018, with Horn fighting someone else in November.

Pacquiao, 38 years old, is at the tail-end of his career and he's been extremely busy with his full-time job as a senator in the Philippines.