Zurich - FIFA President Sepp Blatter has suggested reviving his "6-plus-5" plan to limit foreign players in a club team's starting line-up.
The proposal provoked deep conflict between FIFA and UEFA before being dropped in 2010 as unworkable under European labour law.
Blatter writes in FIFA's weekly magazine that "we have not heard the last word on this subject."
The rule suggests "each club should field at least six players eligible to play for the national team of the club's home country."
Blatter says this would create closer ties between clubs and the national team, help clubs keep their identity, and promote youth training.
However, the 28-nation European Union protects free movement of workers.
Blatter and UEFA President Michel Platini have increasingly traded barbs ahead of FIFA's presidential election in May 2015.