The federal government is reaching out to the provinces and territories to talk about invoking the never-used-before Emergencies Act, as pressure mounts on Ottawa to take control of critical medical supplies and equipment in the fight against COVID-19.

Sources tell CBC News that Ottawa has sent a letter to provincial and territorial governments as part of the consultation period — a required step before triggering a public welfare emergency. The issue also is expected to be a topic when Prime Minister Justin Trudeau calls the premiers today.

Sending the letter doesn't necessarily mean the federal government is poised to invoke the act — but it does mean it's looking for feedback from the regions on such a step.

The letter thanks the premiers for their support and coordination so far.

"Federal ministers of Justice, Public Safety, Health and Agriculture and Agri-food have since spoken to their provincial and territorial counterparts about whether measures under the Emergencies Act could assist our collective efforts to respond to the pandemic," it reads.

One federal source said the letter is part of a contingency plan. Another said that while the federal government doesn't want to infringe on provincial jurisdiction, Ottawa wants to make sure the provinces are aware of what's in the legislation.

The Emergencies Act — which came into effect in 1988 — gives the federal government sweeping powers to regulate or prohibit travel, requisition and use property, order qualified people to provide essential services, regulate the distribution of goods, resources and services and establish emergency shelters and hospitals.

Under the act, Ottawa could redirect medical supplies — masks, ventilators and COVID-19 testing devices — to pandemic hot spots in dire need.

One source told CBC News one of the federal government's concerns has to do with allocating supplies for Indigenous communities.

The number of reported positive cases of COVID-19 in Indigenous communities across the country has more than doubled since last week, according to Indigenous Services Canada, and many fear the trend will bring devastation to some remote locations.

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Appearing before a House of Commons committee Tuesday, Linda Silas, president of the Canadian Federation of Nurses Unions, called on the government to invoke the Emergencies Act to ensure supplies and equipment are deployed to where they're most needed across the country.

"Front line workers across the country who are directly involved in the care of presumed and confirmed COVID-19 patients are not being provided with the [personal protective equipment] they need to do their jobs," she told the committee.

"That's simply outrageous and unacceptable in a world-class health system like ours."

Parliament would need to be recalled

A formal letter to the provinces is a step further than Trudeau has taken in the past. He has repeatedly said the government would look at every tool at its disposal in the fight against the pandemic, but has called the Emergencies Act a last resort.

"We will continually work with jurisdictions, with cities, with provinces on new measures or extra measures that they feel are necessary," said Trudeau Wednesday, when asked about cracking down on Canadians who are not listening to the physical distancing advice.

"We're continually monitoring what is needed and what we might need to do as next steps."

New Brunswick Premier Blaine Higgs has said he favours the federal government invoking the Emergencies Act in response to the COVID-19 pandemic, while Ontario Premier Doug Ford has said it's Trudeau's decision to make.

"Every single province is different, so we want to make sure that we still have the authority to make the decisions that we require for ... the health and the economy in each province," Ford told reporters late last month.

A source said the provinces will have a few days to respond before Trudeau makes any kind of decision.

The Emergencies Act replaced the War Measures Act, notoriously invoked by Trudeau's father, then prime minister Pierre Elliott Trudeau, during the FLQ crisis. Sources say there is some reluctance in the Prime Minister's Office to invoke the Emergencies Act, given the optics involved in two Trudeaus triggering such sweeping laws.

The Emergencies Act includes some major departures from the War Measures Act, however — most notably the requirement that the government needs Parliament's participation in invoking the act.

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If an emergency declaration is made by cabinet, Parliament must be summoned to "sit within seven days after the declaration is issued" — a measure added to the act to avoid abuse by the government of the day.

This Parliament has been temporarily adjourned, but a handful of MPs already have made the trip back to Ottawa to push through, and tweak, crucial measures like the wage subsidy program, and are already in talks about returning again.

The Liberal government also would have to answer tough questions about its use of the Emergencies Act once the crisis is over. Under the act, an inquiry must be held within 60 days of the emergency declaration expiring and a report has to be tabled in Parliament within a year.