Employees at Canadian National Railway (CN) will return to work on August 23, partially ending an unprecedented work stoppage, after intervention by the federal government. Canadian Pacific Kansas City (CPKC) said it was preparing to restart operations, but that the timing was pending.

CN and CPKC on August 22 locked out 9,300 workers after failing to clinch a deal with the Teamsters union.

Now, BBC News reports, the Canadian labor minister has asked the federal industrial relations board to impose binding arbitration on the parties.

In addition to the back-to-work order, Labor Minister Mackinnon asked the Canada Industrial Relations Board (CIRB) — an independent third party — to begin the process of binding arbitration between the Teamsters and both rail companies.

Early on the morning of August 23, the Teamsters union wrote in a statement posted to X that it had taken down picket lines at CN. But the Teamsters also wrote that the work stoppage at CPKC was ongoing, "pending an order" from the CIRB.

The union said it will challenge the constitutionality of a government decision by the CIRB.