By ROB GILLIES and JOSH FUNK

TORONTO (AP) — One of Canada’s two major freight railroads resumed operating Friday, bringing an end to a stoppage that threatened the economy across North America.

Canadian National trains began rolling at 7 a.m. all across Canada, said CN spokesperson Jonathan Abecassis.

Trains operated by the second company Canadian Pacific Kansas City Ltd. remain parked, as the union representing the railways’ 10,000 employees plans to challenge a government order to enter arbitration to resolve a contract dispute.

The Teamsters said the work stoppage remains ongoing, pending an order from the Canada Industrial Relations Board. Another hearing was scheduled for Friday morning, but it’s unclear how quickly the board will issue its decision.

The Canadian government forced the country’s two major railroads into arbitration with their labor union late Thursday afternoon, a move aimed at averting potentially dire economic consequences across the country and in the U.S. if the trains are sidelined for a long period.

The government’s action came more than 16 hours after Canadian National and CPKC locked out workers over a labor agreement impasse. Both railroads said they would work to get trains moving again as soon as possible.

The unprecedented work stoppage led Canada’s labor minister to refer the dispute to the Canada Industrial Relations Board to impose binding arbitration. The union and Canadian Pacific Kansas City Ltd. officials met with the board Thursday and will meet again Friday.

CPKC said it was prepared to discuss the resumption of service at the meeting with the CIRB, but the union refused and wants to make submissions to challenge the constitutionality of Labour Minister Steven MacKinnon’s direction.

The union representing 10,000 engineers, conductors and dispatchers at Canadian National and CPKC Canada responded angrily to the order Thursday, accusing the railroads of intentionally creating a crisis to force the government to intervene.

Teamsters Canada Rail Conference spokesperson Christopher Monette said the union plans to file its challenge to the order as soon as possible, but it wasn’t immediately clear how quickly that will happen. In the meantime, the union plans to hold a rally outside CPKC headquarters in Calgary on Friday morning with the head of the International Brotherhood of Teamsters, Sean O’Brien, and the leadership of Teamsters Canada.

It was not immediately clear Friday morning whether the union members would return to work on CPKC while their challenge of the minister’s order proceeds in court.

The government ordered the railroads into arbitration with the Teamsters Canada Rail Conference to end the lockout that began at 12:01 a.m. Thursday after the two sides were unable to resolve the contract dispute.

“The CIRB is addressing the Minister’s referrals under section 107 of the Canada Labour Code, involving CN, CPKC, and TCRC, with utmost urgency. Case management conferences were held last evening, and a hearing is proceeding today. At this time, no further comments can be provided on these proceedings,” board spokesperson Jean-Daniel Tardif said.

All of Canada’s freight handled by rail — worth more than $1 billion Canadian (US$730 million) a day and adding up to more than 375 million tons of freight last year — stopped Thursday along with rail shipments crossing the U.S. border. About 30,000 commuters in Canada were also affected because their trains use CPKC’s lines. CPKC and CN’s trains continued operating in the U.S. and Mexico during the lockout.

Many companies in both countries and across all industries rely on railroads to deliver their raw materials and finished products, so they were concerned about a crisis without regular rail service. Billions of dollars of goods move between Canada and the U.S. via rail each month, according to the U.S. Department of Transportation.

___

Funk reported from Omaha, Nebraska.