The premier expressed hope for a settlement between CN Rail and the 3,200 striking workers, but called on Prime Minister Justin Trudeau and the opposition parties to pass emergency back-to-work legislation if necessary ahead of Parliament's scheduled return on December 5.

The APQ says that a prolonged strike affecting freight service would not only impact Quebec's propane industry, but the countless businesses and consumers who use the gas.

The reserve will go to hospitals and retirement homes first, as well farmers who depend on propane to dry grains and heat facilities.

"The strike can not last", Legault said in an unprompted statement to journalists in Quebec City. "So I am asking the opposition parties in Ottawa to support Mr. Trudeau if we can not conclude an agreement with the union soon".

Federal Conservative leader Andrew Scheer also issued a statement calling on Trudeau to get CN back to work saying the strike is hurting all aspects of the economy, from agriculture to manufacturing and mining.

Quebec has already begun rationing its remaining propane reserve of 12 million litres and is trying find trucks to bring more of the fuel into the province, Legault said.

Most of Quebec's propane supply comes from Sarnia, Ont.

Quebec started rationing use Wednesday to stretch out the stock.

A strike at Canada's biggest railroad, Canadian National Railway Co, entered its third day on Thursday, as the company said talks were continuing with workers, assisted by federally appointed mediators. "We are prioritizing hospitals, seniors' residences and the agricultural sector".

Lineups lasting up to six hours had already been reported at that location, St-Pierre said.

About 85 per cent of the province's propane comes via rail, the bulk of it from refineries in Sarnia and some from Edmonton - the country's two propane trading hubs. William Van Tassel is a grain farmer in Quebec and a representative of the Quebec Grain Growers Association.

"There are direct jobs that will be at stake in the very near future", Moe said.

The fuel is critical to powering mining operations and heating facilities from water treatment plants to remote communications towers, though "people only think about it as barbecue", St-Pierre said. "When you depend on an infrastructure so important as the rail", she said, "it's hard to have a plan B".