Manchester City have been banned from European club competitions for the next two seasons and fined STG 25million ($A48 million) after being found to have committed "serious breaches" of financial regulations.
The reigning English Premier League champions overstated sponsorship revenue in accounts submitted between 2012 and 2016, according to European football's governing body UEFA.
City said in response they are "disappointed but not surprised" by UEFA's announcement and will appeal against the punishment to Court of Arbitration for Sport (CAS).
"The Adjudicatory Chamber, having considered all the evidence, has found that Manchester City Football Club committed serious breaches of the UEFA Club Licensing and Financial Fair Play Regulations by overstating its sponsorship revenue in its accounts and in the break-even information submitted to UEFA between 2012 and 2016," read a UEFA statement.
The ruling, if upheld, would mean City would not be able to compete in next season's Champions League should they again qualify for Europe's top club competition.
UEFA's FFP rules are intended to prevent clubs receiving unlimited amounts of money through inflated sponsorship deals with organisations related to the owners.
City have been drawn to face Real Madrid in the last-16 of this season's Champions League, with the first leg of that tie set to be played on February 26 at the Bernabeu.
Findings published by UEFA also state that the club "failed to cooperate in the investigation of this case by the CFCB".
Australian Associated Press