France declared a record 10,561 new coronavirus infections within 24 hours as of 2 pm (1200 GMT) on Saturday, national public health authority Sante Publique France said.
The figure comes a day after Prime Minister Jean Castex warned that the situation was deteriorating and appealed to citizens to strictly observe hygiene, distancing and mask rules.
France has seen infections rise sharply in recent weeks after they remained at a low level through much of the summer in the wake of a strict 55-day lockdown that ran from March 17 to May 11.
It was one of the European countries worst hit by the epidemic, with a total death toll of 30,910 as of Saturday.
Castex has also given local administrators in Marseille and Bordeaux, as well as the Caribbean territory of Guadeloupe until Monday to come up with new measures to stall the spread of the virus locally.