A historic union strike against Detroit’s Big Three automakers went into effect early Friday after management and the union failed to agree on a new contract that would include a return of pension plans and a pay raise increase of up to 40%.

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Friday’s walkout signals the first time that the United Auto Workers union has struck against all Big Three automakers at one time.

Biden sending top aides to help negotiations

Update 12:40 p.m. EDT Sept. 15: President Joe Biden said Friday that he is sending acting Labor Secretary Julie Su and White House senior adviser Gene Sperling to help automakers and UAW reach an agreement following a strike that began hours earlier.

“Over the past decade, auto companies have seen record profits, including in the last few years, because of (the) extraordinary skills and sacrifices of UAW workers,” the president said during a news conference at the White House. ”Those record profits have not been shared fairly, in my view, with those workers.”

He urged automakers and workers to return to the negotiating table, saying that automakers “have made significant offers, but I believe that they should go further to ensure record corporate profits mean record contracts for the UAW.”

“The bottom line is that autoworkers help create America’s middle class,” he added. “They deserve a contract that sustains them and the middle class.”

— Theresa Seiger, Cox Media Group National Content Desk

Original report: The workers at three auto plants — a General Motors assembly plant in Wentzville, Missouri, a Stellantis assembly plant in Toledo, Ohio, and part of a Ford plant in Wayne, Michigan — walked out under what UAW president Shawn Fain called a “stand up strike” strategy, NPR reported.

While the union has nearly 150,000 members, only about 13,000 workers are striking for now, union officials said.

“This is our generation’s defining moment,” Fain told UAW members at a Facebook Live event on Thursday night. “The money is there, the cause is righteous, the world is watching.”

In addition to walkouts targeting all three automakers, the UAW also decided to negotiate with all three companies at once, something it has not done in the past. The UAW has promised that more workers will leave their jobs if negotiations break down.

Stellantis, which makes 14 automotive brands, including Chrysler, Dodge and Jeep, said it was “disappointed” following the strike’s launch.

“We are extremely disappointed by the UAW leadership’s refusal to engage in a responsible manner to reach a fair agreement in the best interest of our employees, their families and our customers,” the automaker said.

“We immediately put the Company in contingency mode and will take all the appropriate structural decisions to protect our North American operations and the Company.”

The UAW has called for the restoration of pension plans and healthcare for retirees, cost of living adjustments and a 40% pay raise that Fain says would be in line with CEO wage increases.

“The Big Three can afford to immediately give us our fair share,” Fain told UAW members on Wednesday.

The automakers disagreed.

GM said it made “historic wage increases and manufacturing commitments” and offered an unprecedented economic package in an effort to reach a deal with the union, according to NBC News.

GM is ready to return to negotiations and get people back to work as quickly as possible “for the benefit of our team members, customers, suppliers and communities across the U.S.,” the company said in a statement.

Ford officials said they have tried to avoid the strike and they are “committed to reaching an agreement that rewards our employees” at the same time protecting the company.

“Ford has bargained in good faith in an effort to avoid a strike, which could have wide-ranging consequences for our business and the economy. It also impacts the very 57,000 UAW-Ford workers we are trying to reward with this contract,” they said in a statement late tonight.

“Ford remains absolutely committed to reaching an agreement that rewards our employees and protects Ford’s ability to invest in the future as we move through industry-wide transformation.”

President Joe Biden is expected to speak from the White House about the strike sometime on Friday.