Manchester City have asked the Court of Arbitration for Sport (CAS) to throw out a case claiming they deliberately tried to cheat financial fair play (FFP).
European governing body UEFA launched an investigation into a potential breach of FFP rules in March but the Premier League champions have denied any financial irregularity.
The probe was launched after allegations made in German publication Der Spiegel, purportedly obtained by whistle-blowers Football Leaks, that City circumvented rules by inflating sponsorship deals.
City were referred to the Club Financial Control Body (CFCB) adjudicatory chamber in May and could potentially face a ban from the Champions League or spending restrictions if they are found guilty.
"The Court of Arbitration for Sport (CAS) has registered an appeal filed by Manchester City Football Club (MCFC) against the Union of European Football Associations (UEFA)," a CAS statement read. "The appeal is filed against decisions taken by the Investigatory Chamber (IC) of the UEFA Club Financial Control Body (CFCB) regarding MCFC's alleged non-compliance with UEFA's Club Licensing and Financial Fair Play Regulations.
"An arbitration procedure will now be initiated and will involve an exchange of written submissions between the parties while a Panel of CAS arbitrators is convened to hear the appeal. Once the Panel has been formally constituted, it will issue a procedural calendar.
"It is not possible to say at this time when the Arbitral Award for this matter will be issued. CAS will not provide any further information in relation to this procedure, except to issue a Media Release announcing the Panel's decision."
The club denied any wrongdoing in a statement released in May which said: "Manchester City is entirely confident of a positive outcome when the matter is considered by an independent judicial body."
UEFA has said it will not be making any further comment on the matter until a decision is announced.