US citizens and several other categories of visitors will be exempt from the ban as Canada tries to contain the novel coronavirus (COVID-19) outbreak, Trudeau said.
"We will be denying entry to Canada to people who are not Canadian citizens or permanent residents", Trudeau said. "This measure will carve out some designated exceptions, including for air crews, diplomats, immediate family members of Canadian citizens, and, at this time, US citizens".
Trudeau also outlined other measures, including pre-boarding screening aboard and allowing only asymptomatic individuals on board airplanes.
In addition, he said all inbound international flights, aside from those originating in the United States, Mexico, and the Caribbean, will be streamlined to four airports: Toronto Pearson, Montreal-Trudeau, Calgary and Vancouver.
Trudeau also said that Canadians unable to return to Canada for medical reasons will be provided monetary assistance for care received abroad.
However, those who return from abroad must self-isolate for 14 days.
As of 16 March, Canada has registered 324 confirmed cases of COVID-19 infection - up from 157 on Friday.