Der Spiegel reported last week City and PSG breached FFP rules by €188 million (£164 million) and €215 million respectively in 2014, and tried to cover up the breach using vast sponsorship deals connected to their oil-rich owners that far exceeded their true market value.
Defending the Premier League champions as "incredibly professional" in response to allegations they bent financial fair play rules, he added: "Of course, like many, many clubs around the world they have a lot of money, but they are also an incredible club".
Guardiola distanced himself from allegations of any wrongdoing on City's part, insisting he doesn't get involved in the business side of the club's dealings.
It led to apparent threats of legal action from the club and indignation to the point where City fans still gleefully greet the UEFA anthem with a chorus of boos on Champions League nights. "Of course we want to follow the rules", the City boss said.
La Liga, the Spanish top flight, has said that, if UEFA does not act, it will "launch a complaint with European Union competition authorities".
'If you want to buy your way into football heaven, you can't let a few rules get in the way'.
Der Spiegel claims one of City's solutions to circumvent the rules was to launch Project Longbow.
Documents suggest a company called Fordham Sports Management - allegedly steered by Conservative Party donor David Rowland and his son Jonathan - paid City players for their image rights.
The accusation from Der Spiegel after viewing internal documents is that it was Sheikh Mansour's company, Abu Dhabi United Group, that gave the Rowlands the money "for the purchase of the marketing rights and to pay the players for their marketing appearances".
And while the club have given only a short response to the allegations to date, on Tuesday boss Pep Guardiola insisted City's success is not exclusively down to the money they have spent.
French Uefa president Michel Platini was the man behind FFP. One memo from chief executive Ferran Soriano is said to have read, "We will need to fight this and do it in a way that is not visible, or we will be pointed out as the global enemies of football".
German magazine Der Spiegel released a number of stories based on so-called Football Leaks data alleging City had avoided UEFA's FFP regulations.
It says that Uefa was unaware of the arrangement with the external company and it was only raised when auditors from PricewaterhouseCoopers took a closer look on behalf of the European football governing body. But the magazine said the analyst "was having trouble" figuring out "how the [external company] expected to make a return". The leaks validate what we have been saying for more than a year.