OTTAWA – Company officials and negotiators representing 2,800 striking Canadian National Railway workers returned to mediated bargaining Wednesday with the specter of a legislated return to work looming over a dispute that government fears could cripple the economy.

National Labor Minister Jean-Pierre Blackburn gave official notice that he would table legislation within 48 hours ordering the employees back to their jobs.

“We want to be sure that the population realizes that we are serious,” Blackburn said outside the Commons.

“We urge the parties to get an agreement as soon as possible. If nothing happens, we have to act. This is so important for our economy,” he said.

Blackburn said companies already are closing down, limiting output or laying off workers due to the lack of access to markets and supplies.

Frank Wilner, a spokesman for the United Transportation Union, said union representatives rejected a company request to send the conductors and yard-service workers back to work while the two sides discussed the key issues of safety, working conditions and wages.

Union divisions appeared to bedevil the process. With the dispute’s effects rippling throughout industry, at seaports and in isolated communities, some striking workers were said to have been turned away at the gates of several CN rail yards Wednesday after a former negotiator, Rex Beatty, declared that the walkout had been suspended.

Beatty claimed the decision came in response to requests by Blackburn and mediator Elizabeth MacPherson, in order to avoid a federal back-to-work order.

“We have called upon all our members to effect an orderly return to work,” Beatty stated. “Back-to-work legislation would have a devastating effect on labor relations on the railway.”

But the UTU’s international bosses in Washington said they relieved Beatty of his duties as chief negotiator two days earlier. Two UTU Canadian vice presidents, John Armstrong and Robert Sharpe, were appointed in his place and have rejected the idea of a return to work during a cooling-off period, said union spokesman Wilner.

Wilner added that union officials are disturbed by Beatty’s claim that Blackburn and MacPherson talked to him after he had been removed as chief negotiator.

“We consider that to be improper, outrageous and highly disruptive to the negotiating process,” he said. “It’s near impossible to engage in meaningful negotiations with this kind of chaos going on.”

CN issued a statement saying the company “acknowledges the need for Canadian government legislation to end the labor dispute” amid “intense internal divisions” in the union.

CEO Hunter Harrison said CN would have preferred a negotiated settlement, but now “the federal government must proceed expeditiously with legislation.”

CN also denied blocking the return to work of UTU members, but said it’s in talks with the new union negotiators, not Beatty.

The railway said about 340 UTU members made themselves available for work in the company’s eastern region by noon Wednesday and will be called for assignments when necessary.

When the strike began Feb. 10 after talks broke down, CN said the union wanted a three-year contract with pay raises of 4.5 percent the first year, 4.5 percent the second year and 4 percent the final year. CN said the workers earned an average of $75,000 last year.

On Wednesday, the Mining Association of Canada issued a news release expressing concern about “the significant and growing economic impact of the CN rail strike on mining communities.” It urged the government to intervene, calling the situation in some areas very serious.

“The CN rail strike is causing a shortfall of essential fuel shipments to the diamond mines in northern Canada,” it said. “Timing is critical because the fuel is delivered to the mines on a seasonal ice road that typically closes by the end of March or first week of April due to melting ice.”