Tens of thousands of port workers along the East Coast and Gulf of Mexico went on strike in the early hours of Tuesday morning, the first industrial action by the U.S. longshoremen’s union in almost half a century.

The stoppage could cost the U.S. economy $5bn a day after an “impasse” stalled negotiations over wages and automation.

Port facilities from Maine to Texas were surrounded by walking picket lines in a stoppage that stands to reignite inflation and cause shortages of goods if it goes on more than a few weeks.

AP reports the contract between the ports and about 45,000 members of the International Longshoremen’s Association (ILA) expired at midnight, and even though progress was reported in talks on Monday, the workers went on strike. The strike affecting 36 ports is the first by the union since 1977.

Workers began picketing at the Port of Philadelphia shortly after midnight, walking in a circle at a rail crossing outside the port and chanting “No work without a fair contract.”

The union had message boards on the side of a truck reading: “Automation Hurts Families: ILA Stands For Job Protection.” “We are prepared to fight as long as necessary, to stay out on strike for whatever period of time it takes,” said ILA president Harold Daggett, calling for the USMX to “meet our demands for this strike to end.”

The three dozen affected ports, which stretch from Maine to Texas, together handle one-quarter of the country’s international trade, worth $3tn a year, according to an analysis by The Conference Board, the Financial Times reports.

The business group warned the work stoppage would “paralyse U.S. trade”, halting imports of food, pharmaceuticals, consumer electronics and apparel. The union said it would continue to handle military cargo.

The ILA is described as being the “largest union of maritime workers in North America,” and represents roughly 85,000 longshoremen located along “the Atlantic and Gulf Coasts, Great Lakes, major U.S. rivers, Puerto Rico and Eastern Canada,” according to the union’s website.

Source: