Bob Arum: Manny Pacquiao and Floyd Mayweather Jr fight off

The proposed mega-fight between Manny Pacquiao and Floyd Mayweather Jr has apparently been scrapped after the two sides failed to reach an agreement over drug testing for the contest.

The lucrative showdown had been pencilled in for March 13 in what would have been a box office record-breaker, pitting the world's two leading fighters against each other.

However, Pacquiao recently began legal proceedings against the Mayweather camp after they made certain demands about drug testing which the Filipino claims defamed him by insinuating he has been guilty of doping in the past.

A mediator was brought in this week in an attempt to bring the sides together and save the pay-per-view bonanza but agreement could not be reached, with Pacquiao's promoter Bob Arum claiming Mayweather never wanted the fight in the first place.

"I knew this was going to happen," said Arum.

"There is no chance ever of salvaging it for March. There's no chance for it ever to happen."

In reality there remains every chance the bout could be resurrected with cynics suggesting the row is simply a publicity drive and typical boxing politics.

With the fight seemingly all but agreed, 'Pretty Boy Floyd' insisted upon random blood tests as well as the usual mandatory urine testing which Pacquiao's side, including trainer Freddie Roach, rejected.

Talks on Tuesday continued into yesterday with hopes of salvaging the fight but such optimism proved shortlived as Arum pronounced the bout dead.