The proposed fight between Manny Pacquiao and Amir Khan appears to have fallen apart after a group of investors based in the UAE failed to come up with the promised cash bonanza to stage the fight in the Middle East.

Pacquiao's promoter, Top Rank, had lined up a fight for the Filipino in Brisbane, Australia against the unheralded Jeff Horn but the "Pacman" didn't seem to keen on the bout.

He took to Twitter to ask his fans to vote on an opponent and Amir Khan was who the sizeable majority selected. Although both fighters stated publicly that they had come to terms to fight, the money required has not materialised.

Manny Pacquiao connects with a right to the face of Ricky Hatton. Image: ©INPHO/Getty Images

Last weekend, Keith Thurman and Danny Garcia fought to unify two welterweight titles with Thurman emerging with a close decision and kept his unbeaten record intact.

Pacquiao won the WBO welterwight title off Jessie Vargas last time out so a fight now with the undefeated Thurman would crown an undisputed king at welterweight.

Pacquiao (59-6-2) is entering the twilight of his legendary career but is still a relevant player in the division.

Thurman has notable wins over Robert Guerrero, Shawn Porter and now Garcia giving him a huge amount of credibility should Pacquiao pick him as an opponent. The bout would likely do well on pay-per-view as well given the legitimacy of the bout.