Despite many negotiations, the duo's camps have yet to agree a deal for the bout and Mayweather believes that Pacquiao's promoter, Bob Arum, is to blame.
The American told the LA Times: "No, I don't think it's going to happen later this year.
"It's because of Bob Arum. It's not my fault."
Although the fight is unlikely to be scheduled in the near future, the former world champion's uncle and trainer Roger Mayweather has dismissed Pacquiao's chances.
The trainer said: "There ain't no way that guy lasts five rounds against my nephew."
Miguel Cotto is Mayweather's next opponent, with a bout scheduled for May 5 in Las Vegas.