Dockworkers on Canada’s west coast raised the possibility of a renewed labor disruption at the country’s busiest port after turning down a proposed contract.

Members of the International Longshore & Warehouse Union turned down a deal that would have raised wages by 19.2% over four years, according to a statement late Friday from the BC Maritime Employers Assocation. The union’s leadership had recommended that its members vote in favor.

More than 7,000 dockworkers were on strike for 13 days earlier in July, crippling the flow of trade through the port of Vancouver — Canada’s busiest maritime hub — and Prince Rupert, British Columbia.

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Prime Minister Justin Trudeau’s government sent in a mediator earlier this month to get a negotiated deal done. One option for Trudeau’s government is to recall parliament, which is currently on summer break, to pass legislation ordered the workers to stay on the job.

The dockworkers can now go on strike again with 72 hours of notice. “Regrettably, ILWU’s rejection once again leaves businesses, Canadians and all those who depend on a stable, well-functioning supply chain hanging in the balance,” the BCMEA said. The strike earlier this month snarled more than C$10 billion ($7.6 billion) in shipments, according to the Greater Vancouver Board of Trade.