The Canada-U.S. border will close to all but essential travel midnight Friday, Prime Minister Justin Trudeau announced.
The move to seal off the undefended, shared border of 5,525 miles is a bid to slow the spread of the coronavirus.
Traffic will be limited to essential goods like food and medical supplies that flow back and forth between the two countries. About five million commercial trucks go cross-border annually carrying about CAN$247 billion in goods.
Irregular migrants will now be stopped and sent back, rather than taking them in and isolating them, he said.
Trudeau also outlined other steps in the battle against COVID-19, including having companies switch from their normal manufactured products to producing hand sanitizers, ventilators, and masks.
Canada is "mobilizing industry," he said.
"Our government is working as fast as possible," Trudeau said, to institute changes to fight the virus.
The moves come as Foreign Affairs Minister Francois-Philippe Champagne reported Friday that a Canadian died from complications related to the virus in Japan.
As of Friday morning, there were 873 coronavirus cases in Canada and 12 deaths. Another 13 have recovered.
Meanwhile, the shortage of test kits has some areas limiting them to the most vulnerable people such as health-care workers in hospitals and nursing homes, paramedics and those working in prisons.
"These are groups that we would certainly want to test because we worry about the risk, if they do have the infection, of infecting large numbers of people," said Dr. Tasleem Nimjee, an emergency doctor at a Toronto hospital.
The Public Health Agency of Canada has asked university research departments to donate the materials needed for testing.
"The entire supply chain is fragile in this situation, and both enough (testing) machines and enough staff are problems," said Dr. Allison McGeer at Mount Sinai hospital in Toronto.
Countries closing their borders has decimated airlines. Air Canada said it will lay off about 5,100 employees.
An organization representing Canadian airlines has asked for financial aid, and there are dire predictions that many airlines worldwide could go bankrupt if the drastic flight reductions continue into May.
Trudeau has urged Canadians in other countries to return home and Canadian airline Sunwing is offering free seats to Canadians stuck in various countries.
The first flight dispatched by the government leaves this weekend to pick up Canadians in Morocco, Trudeau said.
But some are also stuck on ships.
Global Affairs Canada said there are 347 Canadians on the Norwegian Jewel and the ship, which is steaming towards Honolulu, has not been able to find a place to dock. It is unlikely Hawaiian officials will allow the ship to dock there, either.
