Thousands of Canadian Pacific Rail employees are off the job across the country.
A work stoppage began over the weekend after the two sides failed to reach a deal.
About 3,000 locomotive engineers, conductors, train, and yard workers are affected.
The Teamsters Canada Rail Conference said CP Rail locked out the workers.
But CP Rail maintains it was the union that withdrew its services before Sunday’s contract deadline.
Wages, pensions, and working conditions are among the major stumbling blocks.