LAS VEGAS — The promoter for boxing sensation Manny Pacquiao says a fight against Floyd Mayweather Jr. will not happen unless Mayweather's camp drops its insistence for Olympic-style blood testing.

Promoter Bob Arum says if that doesn't happen by Thursday, the proposed March 13 fight that would have likely been the richest ever in boxing is over.

Arum accused Mayweather's camp of raising the issue not because they were worried about Pacquiao taking performance-enhancing substances, but because Mayweather never wanted to fight in the first place.

Arum said Wednesday that Pacquiao would agree to testing by the same agencies that test pro football and baseball players, but not for random tests by the U.S. Anti-Doping Agency.

He said that Pacquiao still plans to fight March 13, and will now look for another opponent.