The French overseas territories minister, Francois Baroin, has described the weekend violence at the Goro Nickel construction site in New Caledonia's south as unacceptable.
Kanak activists destroyed vehicles and equipment worth 10 million US dollars amid demands for better protection of the environment.
Work has been suspended indefinitely as the mining company has demanded an assurance from the authorities in the territory to guarantee safety.
Mr Baroin says the vast sites have to be secured better.
"There has to be video surveillance, one cannot leave keys in heavy equipment that makes it easy to set up blockades. There has to be a better performing alarm system to alert - we cannot go on with a situation like this."
About 200 Goro Nickel employees have marched on the French high commission in Noumea in support of action to secure their jobs as the company is set to temporarily lay off its work force of nearly 2'000 staff.