Canadian Prime Minister Stephen Harper said on Wednesday it was unacceptable for striking truck drivers to delay shipments at the country’s largest port in Vancouver, but noted that it was up to the provincial government to deal with the conflict. The labor dispute at the port, a gateway to fast-growing Asian markets, escalated this week just as Harper signed a free trade agreement with South Korea aimed at boosting Canadian exports to Asia. “This is obviously a big problem,” Harper told a business audience in Vancouver when asked to comment on the strike. “As I understand it, unfortunately the labor disputes here are really under the jurisdiction of the provincial government, not ours, but we are concerned about this,” he said. Unionized container truck drivers set up picket lines at the Vancouver port on Monday, joining hundreds of nonunion workers who walked off the job last month in a dispute over pay and services. The dispute has hurt exports of commodities like lumber and specialized grain products, and the import of consumer goods, which the port said would have an impact of about C$885 million ($797 million) per week. “It is not acceptable to have relatively small numbers of people blocking what is important trade for a range of British Columbian and Canadian businesses,” Harper said. The federal government brought in a mediator last week to help with negotiations and to conduct a review on the long-running labor issues. Federal transport Minister Lisa Raitt said she was monitoring the situation closely and called on the provincial government of British Columbia to “take the necessary steps to address the situation.” Raitt has not hesitated in the past to force strikers back to work when it is within the federal government’s power to do so. Last month, she was set to introduce back-to-work legislation to avert a strike by railroad conductors, which the parties ending up resolving on their own. She previously pushed similar legislation to end strikes at Air Canada, Canadian Pacific Railway and Canada Post. Harper said that as Canada’s trade with Asia grows, it needs to expand its infrastructure capacity to deal with increased shipment of goods. “We continue to have challenges on the infrastructure side, particularly as we’re talking about shipping to Asia,” he said.