Canada's freight rail network shut down operations on Thursday, locking out close to 10,000 workers after the country's two operators failed to reach labor agreements, the union said.
"Despite months of good faith negotiations ... parties remain far apart, and both CN and CPKC have began their lockout," Teamsters Canada Rail Conference union said in a statement referring to Canadian
National Railway (CN) and Canadian Pacific Kansas City (CPKC).
The union representing close to 10,000 workers had given a midnight (0500 GMT) deadline to reach a deal.
It is the first time the country has faced simultaneous work stoppages at the two companies, which in the past have negotiated labor deals in alternate years.
CN and CPKC, with tracks from the Atlantic to the Pacific coasts and south into the United States, carry an estimated Can$1 billion (US$730 million) worth of goods daily, including grains and potash, cars and petroleum products, and timber.
Business groups and farmers have warned of costly disruptions to the Canadian economy.
US rail companies and overseas shippers had already stopped accepting some goods destined for Canada in anticipation of a disruption.
The disputes have been around workers' concerns over long hours and fatigue leading to dangerous working conditions.
CN had sought to force the temporary relocation of workers to fill staff shortages in parts of Canada, which the union rejected.
The dispute with CPKC centers on safety issues related to rest periods for train crews.
The two rail operators "have shown themselves willing to compromise rail safety and tear families apart to earn an extra buck", said Teamsters president Paul Boucher.
Teamsters said it remained at the "bargaining table" with the two firms despite the lockout.
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