Shipping in the Canadian city of Vancouver has been disrupted as container lorry drivers go on strike.
As many as 400 drivers joined a picket line on Monday after a near-unanimous union vote to reject a mediated deal.
The union says container lorry drivers have not had wage rise in eight years and suffer increasingly long waiting times when delivering to the port.
A federal mediator has been appointed to review their concerns, but a report is not expected until May.
The union lorry driver strike joined existing work stoppages by non-unionised groups.
The port estimates a lorry driver strikes costs about Canadian $885m ($797m; £479m) a week.
Unifor-Vancouver Container Truckers' Association president Paul Johal told Canadian broadcaster CBC drivers are picketing for higher standardised pay rates to avoid undercutting.
"The cost of living has gone through the roof and there's been no rate increase for the last eight years," Mr Johal said. "We're at a time where we can no longer pull our trucks."
The chief executive for Port Metro Vancouver said in a statement the firm agrees lorry drivers "should be paid a fair wage".
"But bargaining relating to employment and contract relationships can only be done with the employer or the parties to the contract," Robin Silvester said.
"Port Metro Vancouver is not the employer and is not party to the contract relationships."
A spokesman for the union told the Vancouver Sun a deal brokered over the weekend by the federal mediator Vince Ready reviewing the container shipping industry was not enough.
"We think the federal government needs to empower Mr Ready with the ability to bring all parties to the table including the employer groups and talk about what we can do to get those immediate improvements while we wait for the comprehensive review," Gavin McGarrigle said.