The newly agreed restrictions will work alongside Uefa's financial fair play guidelines, making it harder for clubs with foreign investment, like City, to spend their way to success.
"I do not agree," Mancini told the Daily Mail. "If I am a rich man, I want to spend all my money for my team. I don't agree with this in general, but it is only my personal opinion.
"If the rules are this, we should work like this. We can't change this. We need to buy good players. If you want to buy good players you have to spend money.
|TITLE RACE NOT OVER - MANCINI
|17/2||Man City are 17/2 with BetVictor to beat Southampton 2-1
"But if we work quickly, we can find good players without spending a lot of money."
The Italian believes Manchester City are exploited by selling clubs because of their well-known investors, the Abu Dhabi United Group.
He continued: "It is clear with this rule it is more difficult than 10 years ago.
"But if you work well, you can find good players without spending maybe £30m on one player. But it is also true that every time that Manchester City move for a player, if his value is £10m, for City they ask £30m.
"There should be other rules to stop this."