Manchester City and Paris St-Germain “are cheating and should be sanctioned”, according to La Liga following financial conduct allegations.
German news magazine Der Spiegel says City and PSG overvalued sponsorship deals to help meet Uefa’s Financial Fair Play (FFP) rules.
And it says that in 2014 the clubs negotiated with Fifa president Gianni Infantino, who was then general secretary of European football’s governing body Uefa, to agree reduced punishments.
City say they will not be commenting on the claims and that the attempt to damage their reputation is “organised and clear”.
Paris St-Germain have been contacted for a response.
Joris Evers, chief communications officer for Spain’s top flight La Liga, told BBC Sport: “The Football Leaks documents [in der Spiegel] appear to confirm what we have been saying for years. Both PSG and Manchester City are cheating and should be sanctioned.
“We certainly hope Uefa will take the right decisions and enforce Financial Fair Play rules, but we don’t have full confidence that they will.
“Should Uefa fail to act, we will do what we have said before: launch a complaint with European Union competition authorities.”
Responding to the claims, City manager Pep Guardiola said he “trusts the club and what they have done”.
He added: “I’m part of the club, I support the club. We want to do what we have to do in terms of the rules.”