"I chose to further reinforce the measures to reduce our movement and our contacts to strictly necessary ones".
In a sombre address to the nation, the president said that from Tuesday midday people should stay at home and only go out for essential activities.
"People can use our methods to understand the immune responses in larger COVID-19 cohorts, and also understand what's lacking in those who have fatal outcomes", said Katherine Kedzierska, professor of microbiology and immunology at the University of Melbourne, which took part in the research.
"I know what I am asking of you is unprecedented but circumstances demand it".
"We owe the care of their children to our care teams: a minimum service has been implemented, as of today, in kindergartens and schools", said Macron. "We are not fighting against an army or against another Nation. But the enemy is right there, invisible, untouchable, and it is advancing".
Interior Minister Christophe Castaner said 100,000 police would be charged with enforcing the crackdown.
As of Monday morning France had 127 deaths from the virus and 5,423 confirmed cases.
Spain imposes near total lockdown to fight virus
However, the Spanish government stated that the Prime Minister and his wife remain in the Prime Minister's residence in Madrid . In the Middle East, Iran's death toll reached 611, with almost 13,000 infections, including senior government officials.
With particular focus on the elderly, pregnant women and those with pre-existing health conditions, Mr Johnson said people who were considered medically vulnerable should be shielded from other members of the public for 12 weeks.
Macron also said that hospital masks would be rationed for healthcare workers.
The French government will put its new 300 billion euro ($335 billion) loan package through parliament in the coming weeks, but firms will be able to benefit from it retroactively, a Finance Ministry source said on Monday.
Canada also announced it would suspend all travel into the country, allowing only citizens, permanent residents, and Americans to enter. She told Germans to cancel their travel plans.
"This is why we must do everything to slow down the outbreak".
Mr Trump said a nationwide curfew was not under consideration at this point but said the U.S. economy could be heading into a recession.
In a further indication of the new and unprecedented nature of the global coronavirus pandemic, Netherlands Prime Minister Mark Rutte appeared in a televised address to the nation, the first premier to do so since 1973.