Talks planned in New Caledonia yesterday between the CSTNC and the Congress failed to take place because the union leader, Sylvain Nea, didn't join the negotiations to end a six-week strike.
Another effort is to be expected to be made today.
There had been talks last week but no agreement was reached and it was hoped that a solution could be found yesterday.
The union is demanding action on several issues including the high cost of living, the departure of Filipino construction workers employed by the Goro Nickel mining company, and the immediate construction of a nickel smelter in the Northern Province.
Although the territory's main nickel company, SLN, employs no Filipinos, its mines continue to be targetted by CSTNC blockades.
Goro Nickel meanwhile has resumed its work to build a nickel plant in the territory's south after reducing its work force briefly at the beginning of the month.