Uefa last month opened an investigation into allegations, published in the German magazine Der Spiegel, that City illegitimately circumvented Financial Fair Play (FFP) regulations.
Mourinho has regularly complained that United cannot match City’s clout in the transfer market since his arrival in Manchester and pointed to City’s spending power as a reason why United struggle to compete with their neighbours.
Despite Mourinho spending approximately £379m since his appointment at Old Trafford, Pep Guardiola has overseen a £527m outlay over the same period and enjoyed greater success.
United currently sit 19 points behind City, the Premier League leaders and defending champions. The same 19-point gap separated the two clubs when United finished as runners-up last season.
All realistic hope of United winning a first title since 2013 has disappeared after a difficult few months at Old Trafford. Mourinho admitted on Friday that he does not know when the club will be able to challenge again.
Mourinho also claimed that the club may need football’s authorities to clamp down on the spending of their rivals, and though he did not mention City by name, the United manager made a pointed reference to FFP rules.
“It depends on our evolution but also others’ evolution,” he said. “If the ones above us keep going in the same direction and if their ambition and investment is continuous, that’s one thing.
“Another thing is if they stop, or if the Financial Fair Play makes them stop,” Mourinho added. “Then we can close the gap a little bit better.”
City are the only Premier League club accused of breaching FFP regulations. Earlier this week, it emerged that Uefa could ban City from the Champions League as punishment, from as early as next season.
When City’s potential ban was put to Mourinho, he refused to discuss the ‘suggestion’ in detail. “The world is full of suggestions and I never know if they are true or not true,” he said. “That’s not my job to analyse that.”
Der Spiegel’s allegations are based upon information obtained by the Football Leaks operation from internal City e-mails.
City have refused to respond to the substance of the allegations throughout, maintaining that the club will not comment on “out-of-context materials” which were “purportedly hacked or stolen from City Football Group and Manchester City personnel and associated people”
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