General Motors and the striking United Auto Workers hit a roadblock in contract talks on Sunday over the question of moving production from Mexico to plants in the United States, two people close to the talks said.
The union, which has been on strike since Sept. 16, has pressed G.M. to shift production of some sport utility vehicles and pickup trucks from Mexican factories in order to create and secure jobs in domestic plants, these people said.
After the two sides appeared to make progress in recent days, a U.A.W. vice president said Sunday that the union had offered a new contract proposal over the weekend but that G.M.’s response failed to address key concerns.
“We, in this union, could not be more disappointed with General Motors,” Terry Dittes, the U.A.W.’s lead negotiator with G.M., said in a letter to members. “These negotiations have taken a turn for the worse.”
He did not refer specifically to the issue of where G.M. produced cars, but said G.M.’s latest response “did nothing to provide job security” for its American workers.
In a statement, G.M. said it was committed to continuing discussions around the clock to reach a resolution. “We continue to negotiate in good faith with very good proposals that benefit employees today and build a stronger future for all of us,” the company said.
The two sides were continuing negotiations on Sunday, but the tone was growing rancorous. In a letter to the company, Mr. Dittes wrote: “During your response to our proposal delivered at 9:05 a.m. today, Sunday, Oct. 6, 2019, you didn’t even have a professional courtesy to explain why you could not accept or why you rejected our package proposal for each item we addressed. We expect the company to respond and discuss the package proposal we presented yesterday. The law and basic decency require no less.”
By Saturday, the union and the company appeared to have reached agreements on most major issues, including wage increases and a path for temporary workers to become permanent employees, the people close to the talks said. Two unresolved matters, they said, included the time of service required for less senior workers to reach the top union wage — it currently takes eight years — and inflation and cost-of-living adjustments for pensions and 401(k) retirement plans.
But then the issue of moving work from Mexico to United States plants arose as a major stumbling block.
G.M. has three vehicle-assembly plants in Mexico that make S.U.V.s and pickup trucks sold under the Chevrolet and GMC brands. The company’s decision a few years ago to make the new Chevrolet Blazer in Mexico in particular has rankled the union since the midsize S.U.V. is the kind of vehicle that typically can be made profitably in United States plants.
At the same time, G.M. has closed a car plant in Lordstown, Ohio, and engine and transmission plants in Baltimore and in Warren, Mich. A second car plant in Detroit is scheduled to close in January.
The union is pressing G.M. to move some production from Mexico to the idled United States plants. Automakers sometimes move production between plants, but doing so can disrupt production and incur costs for new machinery or moving existing assembly lines.
G.M. has offered to invest $7 billion in United States plants that would create 2,700 jobs and preserve 2,700 others, including keeping the Detroit car factory open. It has also offered to build a new battery plant with a partner near Lordstown that would hire union workers.
“They are down to the toughest issue,” said Erik Gordon, a University of Michigan business professor who follows the auto industry. “G.M. sees it as the flexibility to survive the changes in buyer tastes and from gas to electric vehicles. The U.A.W. sees it as job security for workers who are as worried as G.M. is about the changes.”
The union had chosen G.M. as the negotiating target for this cycle of contract talks with the Detroit automakers in part because the company has been closing United States plants, in contrast to Ford Motor and Fiat Chrysler, and has substantially trimmed its domestic work force.
President Trump, even before taking office, was critical of G.M.’s foreign car production, and shortly after the strike began he reiterated that point. “I don’t want General Motors building plants in China and Mexico,” he told reporters.