Paris Saint-Germain are one of the richest football clubs in the world. 

Backed by Qatar Sports Investments, the Doha-controlled holding company that owns the nine-time Ligue 1 champions as well as Burrda Sport and NextStep Marketing, the French outfit have quickly established themselves as one of the major European powers of the 21st century - snapping up the likes of Gianluigi Donnarumma, Georginio Wijnaldum and Sergio Ramos on free transfers in quick succession.  

And now, Mauricio Pochettino's side are also leading the race to sign former Barcelona star Lionel Messi on a free transfer this summer, according to reports. 

Reliable source Fabrizio Romano has confirmed reports that the Paris-based club are close to a deal with the Argentina superstar, who is currently available as a free agent, as first reported by Sky Sports.  

However, that hasn't stopped the rest of the world from keeping a close eye on their transfer activity this summer.

A Twitter thread from journalist Anthony Lopopolo emerged earlier in the week which reportedly details their frankly astonishing spending so far.   

"How can PSG give Neymar €30M per season, while paying €60M for Hakimi and €75M in pre-tax wages to Messi, Donnarumma, Wijnaldum, and Ramos, and even *think* about re-signing Mbappe in the same year it's expected to lose €204M in revenue? UEFA, just end the charade," he tweeted.

Anthony Lapopolo calls on UEFA to end this 'charade' after exposing Paris Saint-Germain's spending this summer

He later added: "French newspaper L'Equipe in January: 'Selling players becomes Leonardo's main mission.'

"PSG sporting director Leonardo: *yawning face emoji*."

Anthony Lapopolo pokes fun at Paris Saint-Germain sporting director Leonardo

Lopopolo then published a follow-up tweet criticising UEFA for punishing smaller clubs who apparently break the Financial Fair Play Regulations (FFP) while allegedly allowing PSG to get away with the same thing scot-free. 

"UEFA has done absolutely nothing to repair its image as a morally bankrupt organization with zero interest in making the game more sustainable.

"It has punished lesser clubs for far less egregious market activity than PSG's. Many times, perception is indeed reality," he wrote. 

Anthony Lapopolo criticises UEFA for failing to properly act.

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PSG sporting director Leonardo famously fell out with now-Chelsea manager Thomas Tuchel towards the end of last year after being accused of failing to strengthen the squad properly in the previous transfer window.  

Speaking after PSG's 6-1 win over Angers, he said: “If someone is not happy, if he decides to stay, he must respect either the sports policy or the internal rules. 

“You have to understand the moment we are all living through, these are very serious situations. Not understanding this situation, we didn’t like it. Now we’re going to address it internally.

“Everybody has lost millions, it’s weird to talk about it. Nobody is buying, except in England, which is a world apart."

Read more: Lionel Messi and Neymar's best Barcelona moments as Paris Saint-Germain are linked with transfer