Prime Minister Justin Trudeau warned Monday that Canada was “not out of the woods” with the coronavirus, urging citizens to be vigilant amid an uptick in virus cases nationwide.

The country recorded more than 1,300 cases over the weekend — a level not seen since early summer.

On Monday, Quebec and Ontario provinces, the most populous in Canada and the hardest-hit by the pandemic, confirmed nearly 600 cases.

“One of the things we’re seeing is, with numbers rising across the country, we are not out of the woods,” Trudeau told a press conference in Ottawa.

He said the resumption of classes and the reopening of the Canadian economy, meaning more people are back to work, had led to an increase in case numbers.

“The last thing anyone wants is to go into this fall in a lockdown similar to this spring. And the way we can prevent that is by remaining vigilant,” Trudeau said, reiterating the importance of wearing masks and practicing social distancing.

Ontario Premier Doug Ford sounded a warning, saying: “Let me be crystal clear every option is on the table, we will take every step necessary including further shutdowns.”

On Saturday, Quebec became the first Canadian province to fine people for refusing to wear face coverings in enclosed public spaces. The fines run from CAN$400-6,000 (US$303-4,550).

That did not prevent a crowd of several thousand people from protesting against mask wearing in Montreal on Saturday.

As of Monday, Canada had registered more than 137,000 coronavirus cases since mid-March. More than 9,200 people have died as a result of Covid-19.