OTTAWA -- Prime Minister Justin Trudeau is urging Canadians abroad to come home while they still can, as Canada is shutting the border to non-Canadian citizens, with limited exceptions, to limit the spread of COVID-19.

Permanent Canadian residents, the immediate family members of Canadian citizens, diplomats, air crews, and U.S. citizens are still being allowed into Canada at this time. Access to Canada will be restricted beginning March 18, at 12:01 a.m. EDT.

"If you're abroad, it's time for you to come home. If you've just arrived, you must self-isolate for 14 days, and finally all Canadians as much as possible, should stay home," Trudeau said.

Anyone who has symptoms of COVID-19 will not be able to enter Canada. Air operators are being instructed to prevent any traveller who presents symptoms of the virus from boarding a plane.

"I know this news will spark concern," Trudeau said to Canadians who are currently out of the country.

The prime minister said the government will support Canadians currently abroad through a program that will see them either cover the costs to get them home, or cover their basic needs while they wait to return.

Specifically, as Foreign Affairs Minister Francois-Philippe Champagne unveiled later Monday, Canadians abroad impacted by COVID-19 will be eligible for an emergency loan of up to $5,000. For Canadians who can’t find a way home immediately, the government says it will provide support through partnerships with local organizations in addition to existing consular services.

He addressed the nation from self-isolation at Rideau Cottage, updating Canadians on the measures being taken to combat the spread of the COVID-19 pandemic.

Trudeau said the virus has been spreading quickly across the world, and Canada is no exception. Therefore, Canada is taking “increasingly aggressive steps” to keep Canadians safe.

Trudeau announced additional flight restrictions that will also come into effect on Wednesday, that will see some international flights rerouted to Montreal, Toronto, Calgary or Vancouver for dedicated enhanced screening.

Flights from the Caribbean, Mexico and the United States will still be able to land at their planned airports.

The federal government is suggesting all Canadians abroad register with Global Affairs Canada to get the latest updates.

The prime minister said these border restrictions will not apply to commerce or trade, and that products will continue to flow in and out of the country.

He was asked why the United States, where a national state of emergency has been declared on account for the level of spread within that country, has been exempted from Canada's entry restrictions.

Citing the integration of the two countries, Trudeau said that Canada views the U.S. in a separate category from the rest of the world, but the federal government will monitor the situation.

More measures coming

Trudeau said that additional measures will be coming as soon as tomorrow.

"The economic impact of this pandemic is shifting hourly, and we recognize our stress and anxiety that is causing. As I've said, we are prepared to see Canadians through this time. We will have additional measures to announce as early as tomorrow to support Canadians," he said.

"It's time to take every precaution to keep people safe."

Several top cabinet ministers held a media availability on Parliament Hill after Trudeau's address, where the details of the latest measures were discussed.

Deputy Prime Minister Chrystia Freeland, Health Minister Patty Hajdu, Treasury Board President Jean-Yves Duclos, Public Safety and Emergency Preparedness Minister Bill Blair, Transport Minister Marc Garneau each offered the latest from their portfolios.

Because the situation is ever-changing, the response has been evolving rapidly, Freeland said.

"This is not a time to quibble about federal or provincial responsibilities, or about who will pay the bill. Our clear priority is, and must be the health and safety of Canadians," she said.

The ministers were followed by Chief Public Health Officer of Canada Dr. Theresa Tam.

Going forward, there will be a daily update from Health Canada officials, at noon, as well as a daily government briefing for parliamentarians.

Elaborating on the changes like limiting international returns, Garneau said that officials will have to screen passengers before they board.

Further, Blair said that if a passenger is identified as ill, they will be isolated from general passenger processing and will be reported immediately to public health officials.

'Canadians must act now'

Hajdu said given the increase in community transmission in Canada, the number of cases is set to increase, calling the situation "critical" and a "health crisis."

The ministers were followed by Chief Public Health Officer of Canada Dr. Theresa Tam, who emphasized that Canadians should not be gathering in groups with more than 50 people.

"Globally there are now over 175,000 COVID-19 cases in over 160 countries. There continues to be a concerning increase in cases in reported in Canada in the last few days," Tam said.

"All Canadians must act now to take all precautions and practice social distancing in order to interrupt chains of transmission, to delay and suppress the epidemic curve of COVID-19," she said.

Last week, Parliament suspended sitting for five weeks and the Liberals rolled out a $1-billion health and economic response package, as well as an additional $10 billion for businesses who are being impacted by the virus and consumers' changing habits.

Situation calls for 'exceptional measures'

With schools, community centres and businesses shutting their doors in an effort to help contain the novel coronavirus, many Canadians are spending the day indoors, practicing social-distancing or self-isolating.

Over the weekend many employers were evolving their work-from-home policies and municipalities were encouraging their residents to only leave the house if absolutely necessary, leading to concerns from workers who don't have access to paid leave or employment insurance.

“I know that these measures are far-reaching. They are exceptional circumstances, calling for exceptional measures,” Trudeau said.

He said that while it will be an adjustment, all Canadians should stay home if they can, to do their part to limit the virus from spreading and hopefully avoiding an overburdening of the Canadian health-care system.

Throughout the day provincial governments and health authorities have been providing updates on the number of cases in their provinces, with some premiers calling for more action from the federal government, including tightening up the borders.

The prime minister has been self-isolating and working from home since Thursday, when his wife Sophie was confirmed to have contracted the virus. On Monday morning, Trudeau spoke with fellow G7 leaders, where he likely informed them that all foreign nationals will not be able to enter Canada.

When Trudeau began speaking, there were 377 reported cases in Canada. That number rose to 416 an hour and a half later.

Trudeau said that, to date, public health authorities have administered more than 25,000 COVID-19 tests.