Harry Kewell's agent Bernie Mandic believes legal action against Fox Sports commentator Robbie Slater is not ideal.

Slater has alleged that Kewell was told to 'F**k off' by a Australian national teammate at a dinner at the World Cup and that he shouldn't be in the team with the Galatasaray star addressing Slater's allegations via a phone interview on Fox Sports FC the other night.

The interview has sparked plenty of debate and now Mandic has weighed in saying Slater's comments were un-Australian, although he does not want legal action, just the truth.

"We've never ever had an issue with anyone having an opinion, but when you describe a lie as an opinion, now that is the issue," Mandic told AAP.

"Everyone's entitled to their opinion, no problem ... but to actually say that a player said that to Harry when it never happened it scurrilous, it's plain bloody un-Australian.

"If Robbie backs away, there's no point in doing it, all it's doing is filling the pockets of lawyers for no reason.

"But Harry's made his point, I think everybody understands where it's come from but it's very simple Robbie - put up or shut up.

"We've got very strong grounds for legal action but it's not something you want to be doing and getting caught up in and it's the last thing football needs.

"We've been advised that it's a no brainer but we're not about that we're about the truth.

"It would just be nice if the football media of Australia took their job seriously."