Canadian companies faced prolonged shipping headaches Canadian National Railway on Monday walked away from the bargaining table and withdrew contract enhancements it had offered to striking workers.

According to Reuters, the Canadian Auto Workers union, which represents 5,000 striking mechanics, sales clerks and container yard workers at Canada’s largest railway, said it was asking the company to resume talks that broke up late on Sunday.

The news agency said the setback means the 2-1/2-week-old strike, already the longest in more than 15 years at Montreal-based CN, is unlikely to come to quick end, and shippers will face further delays and more scrambling to find alternative transportation.

Canadian transport minister Tony Valeri reportedly said he will continue to monitor the strike closely, but had no intention yet of forcing workers back to work.

DaimlerChrysler Canada told Reuters its operations had suffered only a small impact, but General Motors of Canada reportedly said it could not ship all finished vehicles.

“It’s a big headache right now,” GM Canada spokesman Stewart Low told Reuters, adding: “It really is a lot of jockeying. It’s storing vehicles which we don’t like to do for a lot of different reasons. There’s a cost to that, there’s quality issues because you’re handling vehicles twice.”

CN spokesman Mark Hallman told Reuters the railway has withdrawn a three-part offer and improvements agreed in recent days, walking away from the bargaining table after the union refused to back down on what he described as an “economically unrealistic demand.”