Jorge Horacio Messi claims the Barcelona forward has been part of a media-led witch-hunt.
He told radio station Cope: "I can assure you that what (Lionel) pays every year is an eight-figure sum. We are relaxed because we have never missed a payment to the tax authority.
"It's normal that there's a difference in opinion between the authorities and our advisers, because there always is with people who pay a lot of tax.
"We know that there will be an agreement, but we are angry because certain sections of the media have conducted a slur campaign and tried to whip up hate. It's very cruel, but we will know what to do when this is all cleared up."