The United Auto Workers union is stepping up pressure on Detroit's automakers by threatening to expand its strike unless it sees major progress in contract negotiations by Friday.
In a video statement late Monday, UAW President Shawn Fain said workers at more factories will join those who are now in the fifth day of a strike at three plants.
"We're not going to keep waiting around forever while they drag this out ... and we're not messing around," Fain said in announcing the 11 a.m. Central time Friday deadline for escalating the strike unless there is "serious progress" in the talks.
Ford, General Motors and Stellantis said they want to settle the strike, and they held back from directly criticizing the escalation threat.
Mark Stewart, the North American chief operating officer of Stellantis, the successor to Fiat Chrysler, said the company is still looking for common ground with the UAW.
"I hope that we're able to do that by Friday," Stewart said on CNBC.
General Motors said in a statement, "We're continuing to bargain in good faith with the union to reach an agreement as quickly as possible for the benefit of our team members, customers, suppliers and communities across the U.S."
A Ford spokeswoman said Tuesday that negotiations were continuing, but provided no additional details.
In Washington, the Biden administration reversed a plan to send acting Labor Secretary Julie Su and senior adviser Gene Sperling to Detroit this week to meet with both sides, according to a White House official. Last week, President Joe Biden publicly backed the UAW and said the officials could play a positive role.
The White House now believes that since negotiations are taking place, "it is most productive for Sperling and Su to continue their discussions from Washington and allow talks to move forward," said the official, who spoke on condition of anonymity to discuss the private plans.
Fain had discounted the need for help from Washington, saying, "This battle is not about the president," and some Democrats opposed the White House involvement.
"I do not believe that the president himself should intervene as he did in the railroad strike in these talks. He should not be at that table," said Rep. Debbie Dingell, whose congressional district includes part of southeast Michigan.
Separately Tuesday, Fain responded to criticism by former President Donald Trump, who is expected to visit the Detroit area next week.
"Every fiber of our union is being poured into fighting the billionaire class and an economy that enriched people like Donald Trump at the expense of workers," Fain said. "We can't keep electing billionaires and millionaires that don't have any understanding of what it is like to live paycheck to paycheck and struggle to get by and expecting them to solve the problems of the working class."
In an interview on NBC's "Meet the Press" on Sunday, Trump said Fain and the union were "failing" workers in the shift to electric vehicles that has been championed by Biden.
"The autoworkers are being sold down the river by their leadership," Trump said, adding: "All of these cars are going to be made in China. The electric cars, automatically, are going to be made in China."
Biden has expressed support for the striking workers, although the UAW has not endorsed his reelection thus far. The union has long backed Democratic presidential candidates, but some of its members supported Trump in the last two elections.
So far the strike is limited to about 13,000 workers at a Ford assembly plant in Wayne, Mich., a General Motors factory in Wentzville, Mo., and a Stellantis plant in Toledo, Ohio.
However, the carmakers have warned that there could be layoffs at other locations as the strike crimps the industry's supply chain.
General Motors warned Monday that the strike in Wentzville, near St. Louis, could force the company to idle an assembly plant in Kansas City early this week. On Tuesday, the company said that it expected to keep production going in Kansas City for at least one more day.
The strike could soon begin to affect auto parts suppliers.
United States Steel Corp. said it was temporarily idling a blast furnace in Granite City, Ill., an indication that the company expects the strike to reduce demand for steel. There are about 1,450 workers at the site -- most of them represented by the United Steelworkers, but the company said many workers won't be affected by the furnace shutdown.
That furnace is the only one currently operating at the plant. A local United Steelworkers representative said Monday that about one-third of the union employees there work in the areas that will be affected, where the plant converts ore and pellets into metal slabs.
Temporary layoffs will begin in phases as equipment is idled, U.S. Steel spokeswoman Amanda Malkowski said in an email.
However, even in the portion of the plant that is idled, a certain number of workers will be needed to maintain the equipment and machinery, said Dan Simmons, president of USW Local 1899.
"We'll argue for more people, and they'll argue for less," he said.
Simmons said he'll try to find other assignments within the plant for the remaining workers, but he still expects some will be temporarily laid off.
"There'll be fallout," he said.
The area's congresswoman, Democrat Nikki Budzinski, said U.S. Steel was using the strike as an excuse to idle the furnace. "Their effort to blame this announcement on the United Auto Workers strike is a shameful attempt to pit working people against one another," she said.
A parts supplier, CIE Newcor, told Michigan officials that it expects a one-month closure of four plants in the state to start Oct. 2 and idle nearly 300 workers.
Jose Munoz, president and chief operating officer of South Korean carmaker Hyundai Motor Corp., told reporters Tuesday in Atlanta that auto-parts makers would be disrupted by a long strike. Those problems could hurt production at nonunion automakers, not just the targeted three, he said.
"The way the supply chain works today, everything is interconnected," Munoz said. "It is very difficult to have one supplier that is working only with one [auto manufacturer]. So in a way or another, we will see disruptions in the supply chain which may impact companies over time."
At least 76 publicly traded companies supplied Ford, General Motors and Stellantis in their most recent reporting period, according to data compiled by Bloomberg. Nexteer Automotive is the most exposed with 76% of its revenue coming from the three, the data shows, and at least 21 companies rely on the group for more than a quarter of their sales.
The UAW has pointed to the carmakers' profits -- which the companies recorded as prices rose sharply on strong consumer demand and a limited supply of vehicles because of chip shortages and other issues. The union is seeking wage increases of more than 30% over four years and other sweeteners.
The companies say they can't afford to meet the UAW's demands because they must invest those profits to help them make the transition to electric vehicles.
Information for this article was contributed by David Koenig, Jeff Amy and Joey Cappelletti of The Associated Press, Annika Merrilees of the St. Louis Post-Dispatch (TNS), Redd Brown of Bloomberg News (WPNS) and Neal E. Boudette of The New York Times.