The union that represents workers in three major American car manufacturers announced the start of strike action at three factories at midnight on Thursday (local time), in the absence of an agreement on a new collective labor agreement.

“The strike begins at the three designated plants,” announced the United Auto Workers (UAW), whose head earlier explained that three plants – one from each of the so-called “Detroit Big Three” – General Motors , Stellantis and Ford- for the unprecedented mobilization, calling on the members of the union to be ready to participate in their turn in the strike mobilizations, depending on the course of the collective negotiations.

Sean Fein explained that these are the factories where Ford’s popular Bronco model is produced in Wayne (Michigan), GM’s pickup trucks in Wadeville (Missouri) and Stellantis’ Jeep in Toledo (Ohio). These vehicles currently account for the biggest sales of the “Detroit Three”.

Some 12,700 workers work in the factories.

“For the first time in our history, we’re going to strike in all three of the Big Three,” Mr. Fein insisted, explaining that he was going to the strike rally at the Wayne plant.

He did not rule out the possibility of the strike becoming general.

“If we all have to strike, we will,” he stressed.

If the strike continues, the US economy will suffer: many companies depend on the auto industry and its workers.

The dispute over new collective bargaining agreements could pose a serious problem for Democratic President Joe Biden, who will seek re-election in 2024. Mr. Biden has long called for the fastest possible agreement on new collective bargaining agreements.

The negotiation is tough and the two sides are still far apart. The union is asking for 40 percent raises, the automakers say they won’t go above 20 percent, while rejecting other key UAW demands.

The union has prepared an $825 million strike fund.