Tourism in Paris, one of the world's most visited cities, has plunged due to the coronavirus, sparking fears of mass closures for thousands of businesses that rely on eager visitors from home and abroad, its senior regional official said Thursday.

Fourteen million fewer tourists explored the French capital in the first six months of 2020 compared to last year, Ile-de-France (Paris region) president Valerie Pecresse said.

"Tourism is an extremely precious economic activity for Ile-de-France which represents 500,000 jobs and seven to eight percent of regional growth," Pecresse said at a press conference.

"For the past four years, we had been announcing record number of visitors. So it is with great sadness that we have seen the pandemic shatter an extremely dynamic and flourishing sector," Pecresse added.

The income generated by tourism slumped to 3.8 billion euros ($4.5 billion) over the first six months of 2020 from 10.2 billion euros ($12 billion) in the same period last year.

As many planes remain grounded and long-haul flights limited, 68 percent fewer international tourists visited the city of lights, whereas the drop was of 54 percent for national tourists.

Tourists from abroad tend to spend between twice and three times as much as those who live in France, meaning that the fall in income was that much sharper.

One of Paris's main attractions, the Louvre Museum, said Thursday it had received 75 percent fewer visitors in July and 60 percent fewer in August compared to the same months in 2019.

Nearly eighty percent of those who did come were from France, up from about 20 to 25 percent in other years.

Half of the Paris region's businesses expect an improvement of affairs by the end of October, thanks to French clients and tourists from neighbouring European countries.

But the 80-percent drop in reservations for long-haul flights means many entrepreneurs remain wary.

Pecresse insisted that Paris was a safe destination, and said she was dismayed to learn that Germany and Belgium had designated the region as risky.

The Ile-de-France region is working on a health security label, comprising very strict measures, to reassure foreign tourists, Pecresse added.

French Prime Minister Jean Castex announced on Thursday that face masks will become compulsory  throughout Paris after a surge in cases.

Masks are already obligatory on public transport nationwide and in most enclosed public spaces.