Both Unifor, which represents safety and maintenance workers, and the Teamsters Canada Rail conference union, representing locomotive engineers and other train workers, have issued strike notices that would allow employees to walk off Sunday morning.
A strike would put approximately 5,000 workers off the job and could hamper both freight and passenger train service across the country.
Brian Stevens, National Rail Director for Unifor, said Saturday that several major issues remained to be worked out, but he was "cautiously optimistic" of reaching a deal that would keep Unifor's 1,800 workers from striking.
"It does take two sides to get to an agreement," he said. "We're working at it, but the signs we see from the employer today is that there is a desire to get this thing done."
Teamsters Canada, which represents 3,300 CP rail workers, released a statement by president Douglas Finnson Saturday morning saying there was "no reason why we cannot negotiate an agreement."
A spokesman for Canadian Pacific (TSX:CP) confirmed Saturday afternoon that negotiations with both Unifor and the Teamsters were on-going.
Federal Labour minister Kellie Leitch was in Montreal to participate in the talks. A spokesman stated her aim was to "encourage all parties to work together to quickly reach agreements in the best interest of the Canadian economy and Canadians."
She wouldn't speculate what action the government would take in the case of a strike. However, federal Agriculture Minister Gerry Ritz stated Friday that the government would "look at all the tools they had available" to ensure the economy didn't suffer if a stoppage occurred.
In 2012, the federal government passed legislation to force an end to a nine-day strike by some 4,800 striking members of the Teamsters union and CP Rail employees.
It was estimated at the time that a prolonged strike would cost the Canadian economy $540 million a week.
Stevens said earlier this week that a strike would have an immediate impact on the availability of locomotives and the overall safety and maintenance of the fleet.
"There are safety standards to both the locomotive fleet and the rail cars, and our members are the professionals who are trained and qualified safety and maintenance professionals."
A spokesman for the Teamsters suggested this week any disruption of rail service would have a widespread effect on industries that rely on trains, and that CP managers and other staff would be hard-pressed to maintain service.
Commuter rail service in the Montreal area could be disrupted if a strike occurs. The regional authority Agence Metropolitaine de Transport tried and failed to secure an injunction that would have forced CP to maintain passenger rail service for the 19,000 daily commuters who use the CP-run train routes.
Earlier this week, Canadian Pacific said that in the case of a strike it would "implement its extensive contingency plan by deploying qualified management employees to maintain a reduced freight service on its Canadian network."
There are also separate negotiations taking place between the two unions and Canadian National Railway (TSX:CNR), but neither union in the CN talks has taken a strike vote.
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