The French military will support public services strained by the coronavirus epidemic, President Emmanuel Macron has said, as the country's death toll topped 1,300.
France like other nations has already imposed a nationwide ban on non-essential movement and closed schools and restaurants in a bid to stop the spread of the pandemic.
The military operation, named "Resilience", will focus on "aiding and supporting the population, as well as helping public services face the epidemic in mainland France and overseas", Macron said on Wednesday.
"Unity and courage will allow us to overcome this, we are only at the beginning, but we will hold out," Macron added, declaring that France was "at war".
The comments came after the president visited a military field hospital set up by the army in the eastern Mulhouse region which has been badly hit by the coronavirus.
"The whole nation has been mobilised" in the fight against the disease, said a masked Macron, who also promised more investment for hospitals.
Officials said on Wednesday Paris will also cut metro and train services to a minimum in the capital and its suburbs and close two of its airports as the country expands the lockdown measures.
Operators said the goal was to keep just enough trains running for health workers and others who need to get to work during the coronavirus crisis.
Police are carrying out checks at stations to prevent unnecessary travel, not least by people hoping to escape confinement in large cities.
Also Wednesday, Paris airports operator ADP said it would temporarily shut Orly airport, the main domestic hub, to commercial flights because of the "significant and sudden" drop-off in passenger traffic because of coronavirus travel restrictions.
"Yesterday passenger traffic at Orly was down 92 percent and down 89 percent at Charles de Gaulle," the main Paris international hub, ADP's managing director Edward Arkwright told journalists.
The group had already shut several terminals at both airports as airlines slashed flights.
France has reported 1,331 official coronavirus deaths since the first case was reported in January. More than 11,500 people have tested positive for the virus.
The government will announce over the coming days for how long the country's lockdown measures would continue, spokeswoman Sibeth Ndiaye said.