The domestic carrier Air Caledonie raised its return fares from Noumea by almost $US7 dollars when it restarted its service earlier this month.
The airline was grounded since March because of the Covid-19 outbreak.
The chiefs on Lifou already forced the island's airport to close last Friday, saying it would remain shut until the fare hike was rescinded.
They said the shareholders should wear the extra costs, and not the island's population.
The chiefs on Mare said they would block flights until there was a compromise.