New coronavirus vaccines could be available from the end of 2020 or the beginning of 2021, a presentation by French Health Minister Olivier Veran suggested on Thursday.

French Prime Minister Jean Castex said on Thursday the government must move fast to head off a deadly new COVID-19 wave as the virus's reproduction level has jumped, with infections surging in the Paris region and among young people.

The PM responded to a steep increase in infections with a series of measures including increased testing and compulsory face-coverings in Paris.

The number of "red zones" where the virus is in active circulation has risen from two to 21.

If France did not act fast, the spread could become "exponential", he warned.

A number of European countries are seeing a new surge in cases, and Germany is also planning tighter rules.

French officials recorded 5,429 new infections on Wednesday and Mr Castex said Covid-19 was "gaining ground" across the country.

There was an "undeniable resurgence of the epidemic", he said, with a national rate of 39 positive cases per 100,000 people, four times the rate of a month ago.

Masks for Paris

Promising to do everything to avoid another widespread lockdown, the prime minister said wearing a mask would become mandatory in the capital.

While individual streets and areas in the capital already have rules on wearing face-coverings, this new rule will be far more extensive, covering not only Paris but its inner ring of Seine-Saint-Denis, Hauts-de-Seine and Val-de-Marne.

From 08:00 on Friday (06:00 GMT), all pedestrians will have to wear face-coverings in public areas, as well as people on bicycles, motorcycles, scooters and a variety of other mobility vehicles.

Paris is already a red zone, along with the southern area of Bouches-du-Rhône, where France's second city Marseille made masks compulsory from Wednesday evening.

The whole inner ring is now a red zone too, along with a broad expanse of the southern coastal fringe and the Gironde area around Bordeaux.

(With input from agencies)