The idea won the backing of the FIFA Congress in 2008 but was ditched after it fell foul of European Union laws on the freedom of movement.
"Unfortunately the idea foundered on EU Employment Law - the right to work in the country of choice and individual freedom of movement," said Blatter in his column in FIFA's weekly magazine.
"However, we have not heard the last word on this subject. An Institute for European Affairs (INEA) expert opinion concludes that a "quota agreement" along the lines of the "6 + 5 rule" is compatible with the law. It is therefore not too late to seriously revisit this idea."
Blatter said the rule would solve three problems in one go.
"It would improve the balance between club and national team football, preserve the clubs' national identity and increase the incentive for clubs to make more of their own youth products," he said.
"A glance at the leading leagues in Europe leaves no room for misinterpretation: foreign professionals form the majority in England (60.4 percent) and Italy (54.1), and that makes life hard for home-grown players.
"Naturally, the idea that competition is good for business also applies to football. But it has gone too far when up-and-coming young hopefuls no longer have a chance to prove themselves because foreign employees take their places in the team."
- Sports & Recreation
- European Union