Prime Minister Justin Trudeau’s government tightened travel restrictions meant to contain the spread of the omicron variant of COVID-19 as Canada identifies more suspected cases already in the country.

The government will now require all air travelers into Canada -- from countries other than the U.S. -- to test at the airport, whether they are vaccinated or not, Health Minister Jean-Yves Duclos said Tuesday at a press conference. Canada is also considering new testing rules for travelers from the U.S. by both land and air if needed.

“These rules have always changed over the last 20 months and will continue to change as the situation evolves,” Duclos said.

Foreign nationals who have recently been in Nigeria, Egypt and Malawi were added to the list of travelers banned from entering Canada. The move comes after travel from an initial seven southern African countries was restricted last week.

Canada confirmed its first two cases of the variant over the weekend, both in Ottawa and connected to travelers from Nigeria. Another two cases have been reported in Ontario, as well as one in Quebec and another in Alberta.