Three workers in New Caledonia have been taken to hospital after a clash involving about 100 people at the port in Noumea.
The one-hour fight ended when police intervened in the fight between members of the Kanak USTKE union and employees of the Sato port company.
The incident occurred after the USTKE members lifted a 10-day port blockade aimed at preventing the international Mediterranean Shipping Company from setting up a service between Australia and New Caledonia.
A company representative walked away from talks with USTKE earlier this week, alleging that a racket was being run at the port.
He says he will take France to the European Court of Justice over the way the company is being treated in New Caledonia.