The escalation of squabbling started with La Liga president Javier Tebas publicly launching jibes at Paris Saint-Germain — particularly for signing Lionel Messi.

An enraged response by PSG, a complaint in writing to Tebas, was not going to silence him.

In a letter to PSG seen by The Associated Press , Tebas doubles down on his criticism of the ownership model with funding linked to the Emir of Qatar.

Tebas writes that “PSG's finances have been kept afloat thanks to the multi-million euro contributions of its shareholder over the last three seasons.”

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In the letter addressed to PSG general secretary Victoriano Melero, Tebas makes the accusation that the club's finances “breach the content and, more importantly, the purpose of Financial Fair Play, despite the acquittal by the CAS for technical reasons."

In 2019, the Court of Arbitration for Sport (CAS) upheld PSG’s appeal against an attempt by UEFA investigators to reopen a previously closed investigation.

PSG has been a major target of FFP scrutiny since the launch of the UEFA rules a decade ago — when the influx of Qatari investment began following the takeover by a sovereign wealth vehicle of the Gulf state.

The club forfeited 20 million euros (then $23 million) of Champions League prize money in a 2014 settlement that avoided a more high-stakes legal fight.

During the pandemic, UEFA has eased the rules requiring clubs to break even on its football business, such as on player transfers and wages, and also assesses the fair market value of sponsorship deals.

In writing to Melero, Tebas reasserts long-standing concerns about the number of PSG deals linked to the state, asserting that “sponsorships and other contracts are used that are not in line with market conditions and do not make economic sense."

Tebas roused PSG anger earlier this month with broadsides following Messi's signing after Barcelona could not keep the 34-year-old Argentina star while complying with La Liga's own financial regulations.

Tebas said “PSG looks like the league of legends given the age of some players," sparking the letter from Melero decrying “insulting and defamatory statements."

Showing no sign of backing down, Tebas wrote to Melero to say La Liga officials have now estimated that PSG's wage bill this season will be around 540 million euros — more than 80% of revenue.

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The French league earlier this month also lashed out at Tebas, saying in a statement that his comments “are not worthy of the institution he represents" and pointing to the apparent “financial largesse that Spanish clubs have.”

Tebas has also written back to French league president Vincent Labrune, in a letter seen by the AP, saying the competition has a “reliance on PSG" and maintaining that La Liga has a “very stable financial situation."

Tebas has offered to meet French league and PSG officials to “share with you all of the actions and initiatives that we are developing and implementing in La Liga in order to guarantee the optimum health of Spanish football.”