Supply chain issues are likely to worsen in the coming months after Canadian port laborers struck down a proposed contract that would have ended 28 days of contract disputes.

The 7,500 dock workers of the International Longshore and Warehouse Union have been on strike notice since July 1 but stopped picketing after 14 days at the request of Canada’s Minister of Labor. The workers were striking work at two of Canada’s three busiest ports, the Port of Vancouver and the Port of Prince Rupert.

A number of U.S. companies have been affected by the strike. The Ohio-based Chemical Solvents, which uses one of the affected ports for its Asian imports such as paints and cleaning agents, said significant delays are “going to be a problem” according to CNBC. Both ports are popular destinations for Asian imports because their rail service is faster than the ports of Seattle or Tacoma.