The leader of New Caledonia's Alliance Party says he wants to raise the issue of the electorate's make-up with the French President Jacques Chirac when he visits Noumea in three weeks.
Didier Leroux says the provisions on the subject are not clearly defined in the 1998 Noumea accord on greater autonomy.
The pro-independence faction wants a freeze of the electorate to prevent immigrants from France becoming a majority ahead of future key votes on New Caledonia's status.
But Mr Leroux says such a freeze exists nowhere else and is not compatible with republican principles.
Last month, the French minister in charge of overseas territories, Brigitte Girardin, discussed the separatists' concern during her visit, saying she understood their concern.