Arum told the Telegraph’s Gareth Davies that he feels Britain’s Khan will not get the lucrative fight with pound-for-pound king Mayweather that he has felt would be confirmed since last November.
Khan signed a deal to fight Floyd earlier this year only for confirmation of the bout to be stalled continuously.
Mayweather then published a poll on his website, asking fans whether they want to see him go up against Khan or Marcos Maidana on May 3.
Maidana impressively ended the unbeaten run of Adrien Broner at the tail end of last year, but was defeated by Khan via a unanimous decision back in 2010.
And Arum feels the stringing along of Khan by Mayweather – which is not the first time he has used his position in the sport to play gamesmanship during pre-fight planning – is an abuse of his power.
"What he has done to Amir Khan is absolutely disgraceful, whether he ends up fighting him, or he doesn't," Arum said from Macau, China, where his boxer, Zou Shiming, the former double Olympic gold medallist, fights this weekend.
"My feeling is he is not going to fight him, but it's disgraceful to do that to another human being because you are in a position to do that. Just because he has the power where you can do something like that.
"If a promoter did it, if a Bob Arum or a Frank Warren did it the press would be all over them. They have allowed Myweather to get away with this s***. It's terrible.
"They have twisted the kid in the wind. Mayweather should be ashamed of himself. He's not going to sign the contract. I think he will fight Maidana."
Arum suggests that Khan should at this stage just walk away from the promise of his biggest career payday before it is yanked from under his nose, anyway.
"Cut your ties with these people, be a man," he said.
"You were the great hope of England at one point. I have Olympic gold medal winners with me. The pride with which Vasyl Lomachenko and Zou Shiming carry themselves is astonishing."
Lomachenko, a double Olympic gold medallist who was one of the stars of London 2012, challenges Orlando Salido for the WBO featherweight title next weekend in only his second professional bout.
"These people will never be humiliated like that," Arum added. "Amir Khan has put himself in a position where he can be humiliated. He's like a laughing stock. Terrible. Absolutely terrible.
"He's not fighting back and telling these guys to get lost. Get another promoter, maybe go back to Frank Warren, get another opponent and tell them to p*** off."