Manny Pacquiao's camp says there is no economic sense in setting up a bout with Floyd Mayweather on May 5 after the unbeaten American publicly challenged the Filipino champion via Twitter.

Pacquiao's financial adviser Michael Koncz told The Associated Press on Thursday that a 45,000-seat boxing arena being built in Las Vegas won't be finished before the end of May and staging the Pacquiao-Mayweather fight in a much smaller venue is "foolish from an economic standpoint."

Mayweather challenged and taunted Pacquiao to a May 5 bout in a tweet on Tuesday.

Top Rank promoter Bob Arum has told the Philippines' GMA television the only reason the fight won't happen is if there is an "economic problem."