OTTAWA -- Prime Minister Justin Trudeau says the government of Canada will match all donations to the Red Cross to assist people displaced by the wildfires in Fort McMurray, Alta.

The House of Commons is holding an extraordinary debate on the devastating fire, which is now in its third day and has forced the evacuation of nearly 90,000 people in northern Alberta.

Trudeau says the scale of the fire's destruction has not yet been fully assessed but called it far-reaching and utterly devastating.

The prime minister says Canadians will weather the storm together and together they will rebuild.

Rona Ambrose, the interim leader of the Conservative party, says the citizens of Fort McMurray come from across Canada and have built a thriving resource community that now needs the support of the whole country.

NDP Leader Tom Mulcair called the stoic response of Fort McMurray citizens reassuring and called it "profoundly Canadian" to band together in a disaster.

The government of Alberta has declared a state of emergency in a bid to galvanize the country's relief efforts.