France's presidential palace says President Emmanuel Macron has tested positive for Covid-19.
It said the president took a test "as soon as the first symptoms appeared".
The brief statement did not say what symptoms Mr Macron experienced.
It said he would isolate for seven days, adding: "He will continue to work and take care of his activities at a distance."
It comes as the country has replaced its second national lockdown with a curfew from 8pm to 6am. People will not be allowed out of the house without an authorisation form.
The number of people in France who have died from coronavirus infections rose by 790 on Tuesday to a total of 59,072.
Christmas Eve will be exempt, but the rule will stay in place for New Year's Eve. Bars and restaurants are to remain closed until at least 20 January.
People in France are no longer required to print or download an official justification for leaving their homes during the day.
