The union representing 5,000 employees issued 72 strike notice this weekend and the workers could legally walkout as early as Wednesday.
The two sides are continuing to negotiate and Raitt issued a news release Sunday urging talks or binding arbitration rather than a work stoppage.
But the release didn't give any hint whether Raitt would intervene as she did to block job action at Air Canada and Canada Post.
A spokeswoman for Raitt also wouldn't comment on the possibility.
The workers, represented by the Teamsters Canada Rail Conference, include conductors, trainmen, yardmen, locomotive engineers and rail traffic controllers.
"A disruption of rail services would have a significantly negative impact on businesses and our national economy," Raitt says in the release.
The workers have been negotiating with CP since October to try to reach a new contract _ the last one expired in January.
The union says CP is demanding major concessions on pensions, work rules and wages.
The company says if there is a work stoppage, it will "proceed with a safe and structured shut down of its train operations in Canada."
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