Lyon president Jean-Michel Aulas has accused Paris Saint-Germain of taking advantage of tax privileges afforded them due to their Qatari ownership.
Speaking at the unveiling of new Les Gones signing Maciej Rybus, Aulas blasted the Ligue 1 champions for their treatment of manager Laurent Blanc.
The French coach, who has achieved remarkable domestic success with PSG, is reportedly being laid off for his side's failure to progress beyond the Champions League quarter-finals.
"I read in the press that PSG were considering ending their contract with the coach. I'm shocked," Aulas told reporters.
"When we talk about compensation for coaches who just won three titles, and when this compensation is equal to the global revenue of many clubs in Ligue 1, it concerns me.
"When we are French, we pay taxes like everyone else. When we are Qatari, I understand there are better tax rules than the others."
PSG have strongly denied Aulas' accusations in a press release, which stated: "Following the news and slanderous misrepresentations of Jean-Michel Aulas on Paris Saint-Germain, the club would like to recall that it enjoys no special or privileged tax treatment.
"The club has always been very respectful of all the rules of French law, the French Football Federation and the Professional Football League.
"Paris Saint-Germain invite Jean-Michel Aulas once again to focus his comments solely on the affairs of his club and to refrain from denigrating others, Paris Saint-Germain in particular."