Manny Pacquiao and Floyd Mayweather Jr. have signed off on the major issues in the negotiation for a megafight on March 13, and contracts could be signed in the next few days, a person with knowledge of the discussions told The Associated Press.

Top Rank promoter Bob Arum met with Pacquiao in his native Philippines on Friday and the charismatic champion agreed to terms with only minor changes, said the person, who requested anonymity because the sides agreed not to speak publicly during negotiations.

Arum planned to return to the United States on Sunday and present the amended terms to Golden Boy chief executive Richard Schaefer, the person said. Schaefer is negotiating on behalf of Mayweather and his promotional company.

An announcement could come Tuesday, which would coincide with Arum's 78th birthday.

No site has been determined, but Top Rank plans to send a survey team to Dallas next week to examine the new, $1.2 billion Cowboys Stadium, the person said. Team owner Jerry Jones said Wednesday that the Cowboys "are still desirous of looking at what we can do."

The other possibilities are the New Orleans Superdome and venues in Las Vegas, including the MGM Grand and a temporary outdoor stadium on the Strip.

The fight would be at 147 pounds for Pacquiao's WBO welterweight title, which he won in November with an impressive 12th-round stoppage of Miguel Cotto in Las Vegas.

Michael Koncz, who is advising Pacquiao, said Friday that the contracts need "fine tuning" but declined to elaborate. Koncz added that Pacquiao is "very comfortable" with March 13, even though it is only four months after his last fight.

"Manny has some additional requirements, requests, which Arum didn't think was a problem," Koncz said. "The requests of Manny were so realistic that Arum doesn't feel it's a problem and it's pretty much a done deal."

The bout could be the richest ever, assuming projections are accurate. Pacquiao's fight against Cotto sold 1.25 million pay-per-views, while Mayweather's comeback victory over Juan Manuel Marquez in September did 1.05 million.

The richest fight ever was in May 2007, when Mayweather's split-decision win over Oscar De La Hoya generated 2.4 million buys for $120 million in pay-per-view revenue.

The potential Pacquiao-Mayweather fight certainly would generate widespread international appeal, pitting the flamboyant Mayweather against the man who most believe replaced him on the mythical mantle as the best pound-for-pound fighter in the world.