One of New Caledonia's main pro-independence parties has confirmed it will attend week-long consultations in Paris, called by the French prime minister Jean Castex.
Last month, pro-independence Congress members formally requested Paris to organise the third and last independence referendum under the Noumea Accord.
The Caledonian Union said it would join the Paris talks in two weeks to present its proposed constitution for an independent Kanaky-New Caledonia.
The UNI faction of the pro-independence movement has to date declined to accept the invitation, suggesting instead that Paris could send an envoy to Noumea.
Anti-independence leaders will attend the Paris talks.
The overseas minister Sebastien Lecornu said unprecedented questions lay ahead and there was an urgent need to establish what the outcome of the referendum would mean.
A referendum date has yet to be set, but it must be held by October next year, according to the allowances in the Accord.