The mayor of Saint Etienne is sorry to have seen young defenders William Saliba and Wesley Fofana depart for England last year.
Saliba is now on-loan at Nice from Arsenal, while Fofana is starring with Leicester City.
Perdriau told But!: "Unfortunately, we see that the club sold boys like William Saliba and Wesley Fofana very early on, which I strongly regret.
"The training centre should not be a breeding ground for champions that we sell at younger and younger ages.
"We must be able to keep them, to make them grow, to build a framework. How else do we want to get there?"