Manny Pacquiao’s fight with Amir Khan is off after a promised $38m from an unnamed investment group failed to materialize.

The Filipino boxer and eight-division champion had previously been in advanced talks to fight Australia’s Jeff Horn in Brisbane, but reversed course when approached by a group of investors to fight Khan in the United Arab Emirates on 23 April.

Both Pacquiao and Khan confirmed the fight on their respective Twitter feeds last week, but Pacquiao’s longtime promoter Bob Arum told the Los Angeles Times on Tuesday that the offer was fool’s gold.

“When they contacted me, I told them it was pie in the sky, that this is crazy, it’s not going to happen,” Arum told the newspaper. “Manny wanted to roll the dice. He rolled the dice and it came up snake eyes.

“If something is too good to be true, it’s too good to be true.”

Arum said Pacquiao’s manager Michael Koncz is in the process of delivering a revised proposal for a potential July fight to the 38-year-old fighter, who wants to fight “as soon as possible”.

Pacquiao, who regained the WBO welterweight title with a unanimous-decision win over Jessie Vargas in November, remains the only fighter in boxing history to win recognized world titles in eight different weight divisions.