France's new national lockdown, aimed at curbing the resurgence of COVID-19, may have to be extended beyond its initial deadline of December 1.
The government scientific adviser Professor Jean-François Delfraissy issued the warning late on Wednesday.
Earlier, the French President Emmanuel Macron said that France might start to ease back on lockdown measures once COVID-19 infections fell back to about 5,000 per day from around 40,000 per day at present.
But Delfraissy said he did not think that could be achieved by the start of December.
"By December 1, we will not be at 5,000 contaminations per day. I can tell that to you straight away today. We will need more time," said Delfraissy, who heads the scientific council that advises the French government on the pandemic.
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