New Caledonia's USTKE union has put off its congress scheduled for December because its leader, Gerard Jodar, is serving a nine-month jail term.
Its vice president, Marie-Pierre Goyetche, has told Noumea's daily newspaper that the Congress, due every three years, will not go ahead while the president is in prison.
She described the union decision as exceptional and added it was also exceptional to have a union leader in prison.
Jodar was jailed for his role in strike action at Noumea's domestic airport last May, prompting claims that such punishment would not have been meted out in France.
Marie-Pierre Goyetche also says it's hypocritical to say work is being done on a social dialogue as nobody points out that a union president is in jail.
She also expressed concern that attention is being paid to how outsiders can find a way into the New Caledonian labour markets instead of seeing to how a local citizen can get a job.