Terry Dittes, vice president of UAW's GM department, sent a letter to union members saying an offer GM extended over the weekend "did nothing to advance a whole host of issues".
Normally in contract talks, the union bargains for commitments from the company to build new vehicles, engines, transmissions and other items at USA factories represented by the union.
"It did nothing to provide job security during the term of this agreement", Dittes wrote.
Dittes said union negotiators "could not be more disappointed" with GM's refusal to "recognize the experience and talent of our Membership who make their world-class products and billions of dollars in profits".
"We are committed to continuing discussions around the clock to reach a resolution", GM's statement reads.
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Dalziel has been a GM worker for about 24 years.
"These things are important, that they try to remedy them and find some common ground as quickly as possible", she said. U.S. President Donald Trump and many Democrats have urged GM to shift production to unused or underused U.S. plants. Almost 50,000 workers have been off the job, shutting down 33 manufacturing plants and 22 part distribution facilities nationwide. Parts shortages also have forced the company to close plants in Mexico and Canada.
Despite Dittes' letter both sides continued bargaining Monday.
However, by Sunday, he said the negotiations "have taken a turn for the worse". GM responded to the UAW's proposal at a few minutes after 9 a.m. Sunday morning, said Dittes. The UAW wants GM to make commitments on future products it would build in various plants beyond what has now been offered, said a person familiar with the talks who asked not to be identified. The person, who spoke on condition of anonymity because the talks are private, said both sides are far apart on guarantees of new products in US factories. Of GM vehicles sold in the USA, 22% are produced in Mexico. The spillover impact from the strike has led to plant shutdowns outside of the United States, supplier layoffs and substantially reduced pay for striking workers, who now get $250 per week from the union's strike fund.
GM officials said they have offered to invest more than $7 billion in the United States, add more than 5,400 jobs and improve benefits.