MONTREAL -- Union members are picketing Tuesday morning outside the Canadian National Railway (CN) head office on de la Gauchetière Street in downtown Montreal.

About 3,200 CN chiefs, trainmen and marshals have been on strike since last Tuesday after their collective agreement expired on July 23.

The union says it is concerned about fatigue caused by long work hours and what it considers to be dangerous working conditions.

According to the Teamsters Union representing the workers, no substantive progress has been made at the bargaining table, which is being held in Montreal in front of federal mediators.

In a statement released on Monday, CN management insists it is committed to working with mediators to reach a fair deal.

The carrier adds it has proposed solutions to end the strike and continue negotiations without harming the economy.

It suggests union members return to work and submit their remaining disputes to voluntary binding arbitration, which, according to the employer, the union has so far refused.

CN maintains it only has enough qualified executives to safely provide about 10 per cent of its normal service over 22,000 kilometres of its Canadian network.

It says it is also aware of a recording published by the union, where a worker allegedly complains of fatigue when asked to take control of a convoy and his supervisor replies that he will be sanctioned if he refuses. CN says it is looking into the matter.

Quebec farmers running low on propane gas because of the strike have also been demonstrating over the last few days in hopes that the conflict will be resolved.

At the Port of Halifax terminal, dozens of layoffs are expected to be made on Thursday due to a slowdown in activity caused by the labour dispute.