Gareth Bale
Real are in more financial difficulty that Perez is willing to reveal. (Reuters)

Real Madrid president Florentino Perez has been guilty of understating the sheer size of the club's debt after the revelation that the La Liga giants' grim financial position motivated the sale of Gonzalo Higuain and Arsenal's record signing Mesut Ozil.

Carlos Mendoza, president of the Association for Madrid's Values found himself interrupted by Real's outspoken president at a recent club members' meeting when he attempted to address some of the club's financial misgivings.

Rather than let the Real chief illustrate his own depiction of the club's economics, Mendoza has revealed in an interview with Spanish newspaper AS the severity of the club's concerns.

While acknowledging the fact that Forbes recognises Real as the world's richest club and highlighting the club's lucrative revenue streams, he stresses excessive expenditure poses grave concern within a club model that is "inefficient."

"I was saying (before interrupted by Perez) that the club's debt is €541m, which is the total of long-term and short-term debts. Florentino only recognises the net financial debt, that which is owed just to the banks, which is around €90m," Mendoza said.

"But of course, Madrid has debts with other parities other than the banks, with players, with clubs, with sporting institutions, with the government and public bodies, with suppliers... The total is €541m, more than double the amount Florentino inherited from Lorenzo Sanz (Real Madrid's previous president.")

"On top of that debt, he wants to rebuild the Bernabeu, which he says will cost €400m. Then he says he can't finance it and he'll have to come up with clever strategies."

Perhaps most worryingly for Madrid, Mendoza's projection does not include the £138m the club spent this summer on Asier Illarramendi, Isco and Gareth Bale. Those fees will not come into play until next year's accounts are released, which coincides with the introduction of UEFA's Financial Fair Play regulations.

Although the club have avoided admitting they were left with little choice to offload some of their assets after their exorbitant summer, the sale of Ozil and Higuain in addition to the release of Kaka suggests the club had little choice but to cut costs in some fashion, something Mendoza believes to be a mere drop in the ocean given the club's ever-increasing costs.

"They had to sell him (Ozil) to make up for the signings, just like with Higuain. With that they got a reserve they could use to dress up the accounts for next year. Remember the sale of Kaka has a very negative effect on the accounts.

"They were still two years of his contract to amortise. That's €20m of cost, plus Bale, Illarra, Isco and the salary increases. Ozil was cheap and they sold high, which is good for the accounts, but the overall costs keep increasing and the debt builds up.

"What the club needs to look at is the efficiency of the model. Since Del Bosque left Florentino has spent €800m on players who have won a League and a Cup. The model is clearly inefficient."