Arsene Wenger has cast doubt over UEFA's new financial fair play rules, saying that they may face opposition from a new generation of wealthy owners.
Wenger highlighted the case of Manchester City, who last week announced losses of £195m for the most recent financial year.
UEFA plan to limit the amount of loss that clubs can make, amid concerns that subsidised overspending is inflating players' wages and edging clubs close to financial ruin.
"I am now more nervous about the rules having teeth," the Arsenal boss said.
"When I see the numbers announced by Man City, do you really think it will work in 2013? I cannot see it when the wage bill is bigger than the turnover. Frankly, that cannot happen in one year."
Wenger also raised concerns about UEFA being able to enforce the new rules.
"We live in a world where any decision made is challenged legally," he said. "UEFA want to stop clubs with those sorts of deficits playing in the Champions League. That's in their plan.
"But I question whether they will be capable of forcing it through. Will they have the legal powers?
"In other countries you now have Paris Saint-Germain and Malaga with Qatar owners. Once they represent a force together, it will be difficult to fight against."
Manchester City have insisted that their recent losses would not be repeated in the future.