The two fighters, who are considered by many to be the best pound-for-pound boxers on the planet, have long been unable to reach mutually acceptable terms for a potentially record-breaking pay-per-view fight.
'Money' Mayweather has said that 'Pac-Man' is becoming desperate after his controversial loss to Timothy Bradley in June.
"In my opinion, Manny Pacquiao is desperate," said Mayweather.
"He doesn't make his own decisions because Manny Pacquiao has a boss, his promoter. Once you take a loss, [then] you're on the decline.
"Listen whether he got cheated or not [against Bradley] his stock has dropped enormously since taking a loss. No matter how you took a loss, you still took that L."
Pacquiao returns to action on December 8 as he fights Juan Manuel Marquez for a fourth time at the MGM Grand in Las Vegas, Nevada.