France has sent a 32-strong team of firefighters to New Caledonia just days after the authorities in Noumea declared a fire ban.
More than 60 square kilometres of vegetation has gone up in flames since mid-September, with a sharp acceleration in recent days as 40 uncontrolled fires were started.
The French high commission says the reinforcements are due Friday morning amid warnings that the situation is alarming with the arrival of hot and dry weather.
The boost will also involve the deployment of a fifth helicopter.
Officials say after a rainy winter season, there is plenty of vegetation prone to be burnt, especially along the west coast of the main island.