But since Pacquiao is already on the record as agreeing to all terms for a long-anticipated showdown that can be fought at MGM Grand in Las Vegas on May 2, he thinks Mayweather can do the same by the end of the month.
If not, Pacquiao told the Los Angeles Times on Monday, he's prepared to move on.
"My promoter and I, we've already agreed to the terms and conditions of whatever he wants. We're just waiting on the signed contract from him," Pacquiao said. "That's the hard part – if they will fight or not. We have to know soon, because if they will not fight, we can move on and choose another opponent.
"We have a deadline … this month."
In a visit to the newspaper to promote his new documentary film, "Manny," narrated by actor Liam Neeson, and to be released nationally at selected theaters and on-demand Friday, Pacquiao said "I don't have an idea" if the super-fight will happen.
"The fans deserve this fight," Pacquiao said. "No more will people bother me, 'Can this fight happen?' It's time to make it happen. We're waiting on a signed contract from him."
Negotiations for a Mayweather-Pacquiao fight have collapsed for multiple reasons since early 2010, when both of the world's top two pound-for-pound fighters first sought to make a deal.
Mayweather is still unbeaten at 47-0, and Pacquiao said his six-knockdown drubbing of Chris Algieri in November in China proved to him that he's "still on that level, still hungry for winning."
They're 1-2 in boxing's pound-for-pound rankings and some close to the talks say they've never been closer to a deal.
Mayweather and Pacquiao have agreed orally on the purse split, believed to be 60-40 in Mayweather's favor, and on Olympic-style drug testing.
The hang-up now, according to an official close to the negotiation but not authorized to speak publicly, is how Showtime (which televises Mayweather fights on pay-per-view) and HBO (which broadcasts Pacquiao bouts) can agree to broadcast the fight jointly.
Another official said CBS Chairman
"My job is a boxer – to know how much I get and prepare for a fight," Pacquiao said. "We just want to make that fight happen -- for the sake of the fans, for the sake of millions of people around the world who are excited to see that fight."
He's agreed to what he needs to agree to, Pacquiao said, and hopes Mayweather will do the same.
"The challenge is … we know he's undefeated and claiming he's No. 1 pound-for-pound in the world," Pacquiao said. "I just want to prove who's really No. 1. If the fight is on and he beats me, I'm really convinced he is No. 1. If not, I'm No. 1."
If the worse happens, and Mayweather talks fall apart again, Pacquiao said Amir Khan and "a lot of boxers" are interesting possible opponents, although the boxing public – as seen in Mayweather and Pacquiao's decreasing pay-per-view sales -- is badly tiring of anything less than the big fight.