By David Shepardson and Joseph White

DETROIT (Reuters) -The United Auto Workers expanded its strikes against Detroit automakers General Motors and Chrysler parent Stellantis, but kept its Ford walkout limited to a single plant due to progress made in talks, the union said on Friday.

The auto workers’ union began strikes at noon EDT (1600 GMT) on Friday against 38 parts distribution centers across the United States at GM and Stellantis, extending its unprecedented, simultaneous strikes that began with one assembly plant each of the Detroit Three. The additional facilities added about 5,600 workers to the 12,700 already on strike.

UAW President Shawn Fain said in a Facebook live event that by targeting distribution centers the strike becomes a nationwide event. He said he expected talks to continue through the weekend.

Hours after Fain invited President Joe Biden to visit a picket line, Biden said in a social media post on X, formerly known as Twitter, that he would come to Michigan on Tuesday “to join the picket line and stand in solidarity with the men and women of UAW.” He added: “It’s time for a win-win agreement that keeps American auto manufacturing thriving with well-paid UAW jobs.”

The president has been vocal in his support for the union’s demands for better pay and benefits.

Former President Donald Trump, who is seeking a new term, will be in Michigan on Wednesday to address auto workers, his campaign said.

Fain said the decision on the expanded strike would impact consumers trying to obtain repair parts. The distribution centers are warehouses that ship parts to dealers and other retailers for use in repairs. “We will be everywhere from California to Massachusetts, from Oregon to Florida.”

At a GM parts distribution center outside Philadelphia, picketing workers said the strike will result in cars sitting longer for repairs but that is the only way to get the higher wages they seek.

“If you look at the past few years, car prices went up 30% but our wages went up 6%. We are not the problem,” said Thomas Morris, 60, who has worked at the center in Langhorne, Pennsylvania, for the past four decades. “I understand it’s going to cost some pain for people, but we are just looking for fairness.”

Fain said they have more work to do at Ford, but “we do want to recognize that Ford is showing they’re serious about reaching a deal.” He added: “Stellantis and GM in particular are going to need some serious pushing.”

He also threatened more action at Stellantis’ critical parts plants in his hometown of Kokomo, Indiana. Stellantis has four factories in Kokomo that make engines and transmissions used widely across the automaker’s product line.

Stellantis has said it wants to be able to consolidate and close some of its parts distribution centers.

Fain said Ford had improved its contract offer, including boosting profit sharing and agreeing to let workers strike over plant closures but said the union still has “serious issues” with Ford.

GM said in a statement that UAW leaders are “manipulating the bargaining process for their own personal agendas” and called the strike escalation “unnecessary.” Stellantis said on Thursday it made a “very competitive offer” and said the union’s leadership seems “more concerned about pursuing their own political agendas.”

GM, which said it had contingency plans it did not specify to protect its business and customers, said it has made five separate offers to the union.

Ford said it is continuing to negotiate, adding that “we have more work ahead of us before we can reach an agreement.”

Nearly 13,000 UAW workers walked out at plants in Missouri, Michigan and Ohio on Sept 15. Those plants produce the Ford Bronco, Jeep Wrangler and Chevrolet Colorado, alongside other popular models.

But Ford and Canadian union Unifor reached a last-minute deal to avoid a walkout on Tuesday. Unifor’s Ford leadership unanimously endorsed the tentative agreement late on Friday. Ratification meetings for members were set for Saturday, Unifor said.

Wedbush Analyst Daniel Ives said this latest move by the UAW marks a divergence in the talks with the automakers.

“The current deal is a torpedo to the business models of the Detroit 3,” he said. “To take a deal just to avoid a strike and get it done is great for the next 24 hours but a nightmare for the next 30 years.”

Sam Fiorani, vice president of global vehicle forecasting at AutoForecast Solutions, said Ford’s family-controlled structure gives it a different focus than the other two.

“GM and Stellantis are looking at stockholder value and Ford is looking a lot more long-term that they have to make friends with labor.”

The standoff is fueling worries about prolonged industrial action that could disrupt production and dent U.S. economic growth. A Reuters/Ipsos poll released on Thursday showed significant support by Americans for the striking auto workers.

The automakers have proposed 20% raises over 4-1/2 years, while the UAW is seeking 40%.

The union also wants to eliminate wage gaps separating newer and older employees, as well as workers in certain component operations and those in assembly plants. Fain said on Friday that the union had negotiated the elimination of lower wage tiers in some components facilities at Ford and GM. But Stellantis has not agreed to raise wages at its MOPAR component operations, Fain said.

(Reporting by David Shepardson in Washington and Joseph White in Detroit;Additional reporting by Jarrett Renshaw in Langhorne, Pennsylvania, Ben Klayman in Detroit, Peter Henderson and Abhirup Roy in San Francisco, Jeff Mason in Washington and Kanjyik Ghosh in Bengaluru;Editing by Peter Henderson, Nick Zieminski, Matthew Lewis and William Mallard)

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