German magazine Der Spiegel, using material purportedly obtained from the whistleblowing outlet Football Leaks, alleged in November that Abu-Dhabi backed City had set up sponsorship deals to circumvent regulations limiting how much money owners can put into a club.
UEFA announced on Thursday those claims were being investigated and should they be found guilty, the English champions could be hit with a ban from the Champions League.
City responded immediately by saying they supported the investigation and that they had nothing to hide.
“Manchester City welcomes the opening of a formal UEFA investigation as an opportunity to bring to an end the speculation resulting from the illegal hacking and out of context publication of City emails,” the club said in a statement.
“The accusation of financial irregularities are entirely false. The club’s published accounts are full and complete and a matter of legal and regulatory record.”
One of Guardiola’s biggest challenges when he took charge of City in 2016 was to lead the club to win the Champions League for the first time.
The former Barcelona and Bayern Munich boss has seen his side eliminated in the last 16 and quarter-finals in the past two seasons, but they are favourites to win the competition this year and hold a 3-2 lead over Schalke from the first leg of their last 16 tie in Germany.
“I think the club made a statement yesterday. I can’t add more than that,” said Guardiola on Friday.
“The club is open and hopefully it can finish as soon as possible. I trust what the club has done because I know them.
“Hopefully it can be solved as soon as possible.”
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