However, Kieran Maguire, a senior teacher in accountancy at the University of Liverpool, says the accepted accounting practice of amortisation – spreading transfer fees across the length of a contract – combined with City's ability to make profit on fringe players will help them to balance the books.

"If you've got a £100m signing in Jack Grealish and he signs a six-year contract, you take one-sixth of the transfer fee as the cost each year. So it's only costing them £16m a year as far as their accounts are concerned.

"They have also just shifted (Sergio) Aguero off the books, so that's £250,000 a week in wages, so the acquisition of Grealish will be wage-neutral.

"They have sold Angelino, they have sold Jack Harrison and they get a percentage of the fee from Jadon Sancho going to Manchester United from Dortmund. So actually they have got quite a lot of money coming in from player sales and wage savings, so that's how it will be done.

"There is talk about Bernardo Silva going for £50-60m somewhere in Europe and if they do that then they can easily afford Grealish, and Harry Kane as well.

"If Harry Kane signs for £150m on a six-year contract, that's £25m a year as far as the accounts are concerned.

"They have got to do some forward planning of sales each year, but City are good at that because they have got lots of good young players who have never got anywhere near the first team.

"They are like a factory farm of young talent and these players are being sold for three, four, five million each. You just do a few of those and that covers your increased cost in terms of your elite players."

He added: "Three years ago City spent £328m on players and Chelsea have spent £250m at least twice. This is not without precedent, it just hasn't been concentrated in a couple of players, it's been spread over five or six."

The Premier League's profitability and sustainability rules (PSR) allow for losses of up to £105m over a three-year period. The March 2021 assessment was extended to cover a four-year period due to the difficulties and uncertainties created by the coronavirus pandemic.

There are allowable 'add backs' to a club's profit and loss, such as spending on youth, community and women's football, which may mean a loss of over £105m is ultimately assessed to be under that figure with the add-backs taken into account.

A court ruling last month revealed the Premier League was still investigating City for alleged breaches of FFP rules in the past. The investigation was sparked by leaked material which appeared in German magazine Der Spiegel, which also led to a separate UEFA probe.

The independent Club Financial Control Body (CFCB) of UEFA imposed a two-year Champions League ban on City in February last year but five months later the Court of Arbitration for Sport (CAS) overturned the sanctions.

CAS found that most of the alleged breaches were either not established or were time-barred.

UEFA is consulting over a new approach to financial regulation. Its annual benchmarking report, published in May, said the "precise nature" of regulation had not yet been agreed but stated that wages and transfer fees "must be reduced to acceptable levels".

The report accepts the current FFP rules, in particular the need for clubs to only spend what they earn, "were not designed to counter the consequences of a global crisis".

Asked how UEFA's rules might change, Maguire said: "It could look at some sort of cost control rather than a break-even model, and some form of wage cap.

"But I'm not sure that would work in Europe because you have got 25 different tax regimes. It all gets very messy.

"They have to be very careful because if they try to introduce a European wage cap, somebody is going to go to the European courts and say 'this is a restraint on trade', and our friends in the legal and accounting professions will be looking at their Range Rover brochures on the back of that, because it's going to run and run and be incredibly lucrative.

"UEFA have to be incredibly cautious.

"Ultimately, if somebody wants to spend a lot of money on football it's very difficult to stop them because a) they have got the money and b) they can afford the lawyers to ensure they can do what they want."