UEFA's Club Financial Control Body (CFCB) will review its decision to clear French champions Paris Saint-Germain of breaking Financial Fair Play (FFP) rules after last year's transfer spending spree, European football's ruling body said on Tuesday.
PSG, who signed Brazil striker Neymar for €222 million, also sealed an initial loan move for France forward Kylian Mbappe from Monaco in a deal media reports suggested would be worth €180m when they buy him.
However, the club were cleared of breaking FFP rules last month following a UEFA investigation.
"In light of the decision of the CFCB chief investigator to close the investigation into PSG, the chairman of the CFCB has decided to send this decision for review by the adjudicatory chamber," UEFA said in a statement.
"This announcement does not pre-judge in any way the result of the review to be conducted by the adjudicatory chamber of the CFCB," it added.
FFP rules ban clubs from spending more than their generated revenue, a policy introduced to prevent rich owners from trying to buy success and distorting the transfer market.
Teams can be thrown out of European competition for breach of rules but UEFA has in the past negotiated settlements with offending clubs.
In response, PSG said they have completed various transfers in the past few days, which has seen them comply with UEFA's FFP guidelines.
"The club has been informed of the Adjudicatory Chamber of the CFCB's request to review the decision taken by its chamber of investigation on June 13th 2018 to close the investigation, an official statement read.
"The club outlines that it has succesfully carried out an important number of transfers in recent days in compliance with the CFBC's decision and that it will continue, as it has done since September 1st 2017, to provide all information requested by the CFCB and UEFA."