The New Caledonian government has ordered the closure as of tonight of public places, such as restaurants, bars, nakamals and casinos, for two weeks.
Several new measures have been announced after two people with coronavirus were diagnosed yesterday.
Meetings of more than 20 people will be banned and all events like sport activities and churches have to be cancelled.
Schools will be closed as will be training institutes and the university.
Public transport to and from the Loyalty Islands will be stopped.
The president Thierry Santa urged employers to arrange for work to be done from home if possible.
Non-residents won't be allowed to enter New Caledonia while passenger traffic between New Caledonia and Wallis and Futuna will be suspended.
Meanwhile the French overseas minister Annick Girardin advised people from French overseas territories living in France not to go back to their home islands.
However she said people living in overseas territories who happened to be in France could return but would be subject to strict self-isolation on arrival.
Ms Girardin said basic airlinks were being assured by commercial carriers.