By Edward Chaykovsky

A few months back, former world champion Amir Khan (31-4, 19KOs) accused Top Rank's CEO Bob Arum of being bitter because Khan is not affiliated with his promotional banner, and that is part of the reason - according to Khan - that a fight with Manny Pacquiao (58-6-2, 38KOs) has not come off.

Pacquiao vs. Khan was in talks last year, but then a fight was finalized between the Filipino superstar and Floyd Mayweather Jr. There was also discussions earlier this year, and Khan was passed over in favor of Timothy Bradley.

Pacquiao returns to the ring on Saturday night when takes on WBO welterweight champion Jessie Vargas at the Thomas & Mack Center in Las Vegas.

Khan, who once trained side by side with Pacquiao and sparred with him on numerous occasions, was knocked out in six rounds when he moved up to 155-pounds to face Saul 'Canelo' Alvarez in May.

In an interview with BoxingScene.com, Arum lashed out at Khan, stating that he was overpricing his worth when the two sides were negotiating the financial terms for a Pacquiao fight.

"Khan doesn't have the greatest chin and he makes mistakes - and he's not a top fighter. The truth is - he's not. He makes believe that he won the gold medal in the Olympics but he only won the silver," Arum told BoxingScene.com.

According to Khan, Arum is just scared of what would happen in the fight.

“There are talks about Manny but Bob Arum doesn’t want to make that fight," Khan told Sport360. "It seems to me, he knows what would happen in that fight. It’s a big fight which fans would want to see but I think he is looking for every excuse not to make it. I think he’s scared and it’s also because I’m not with Bob Arum, I’m with a different team, I’m with Al Haymon. I think Bob’s always been bitter against me, he’s always had the bitterness against me."

As the fight with Vargs approaches, Pacquiao has confirmed that he would be open to a fight against Khan. He personally sees no problem with stepping in the ring with the Bolton boxer.

"I'm willing to fight anybody," Pacquiao told Sky Sports News HQ. "Amir Khan is my friend and it's good to fight somebody that you know. That's better."