France's highest court has ruled that those eligible to vote in New Caledonia's provincial elections must have been enrolled since 1998.
The ruling comes amid controversy over who was allowed to choose the assemblies last year, with the pro-independence camp claiming more than 6,000 took part in the vote illegally.
The restrictions are part of the 1998 Noumea Accord on greater autonomy which is to lead up to an independence referendum by 2018.
Magistrates are due from France this weekend to help special commissions vet the voter lists.
The ruling also says that long-term residents who weren't enrolled in 1998 can still vote if they can prove ten years' consecutive residence in the territory before 1998.
The French constitution was changed in 2007 to accommodate the restrictions.