A dust-up between has been talked up for around five years, but the respective fighters' camps are yet to reach an agreement over a potentially record-breaking bout.
Arum thinks that Mayweather's deal with American broadcasters Showtime makes it too easy for the unbeaten 'Money' to continue to avoid a meeting with the Filipino.
He told The Telegraph: "I don't think Mayweather will ever agree to fight Pacquiao, particularly as he has that cushy deal with Showtime. He makes money fighting anyone.
"You talk about a southpaw like Manny, that's not the kind of opponent that Mayweather would do well against."