The United Auto Workers filed a lawsuit Tuesday seeking to block General Motors' plan to shutter three factories as part of a cost-cutting plan announced late last year.
The suit, entered in a US court in the state of Ohio, alleges the US automaker breached its contract with the union when it announced on November 26 that five North American plants would be "unallocated" in an overhaul to phase out underselling models, effectively shutting the plants.
The union asserts that plans to close plants in Ohio, Michigan and Maryland prior to that date violate a 2015 labor agreement, saying "there is no material difference between unallocating a plant and idling or closing a plant."
UAW President Gary Jones said the lawsuit is part of its commitment to "leave no stone unturned" to protect workers' rights.
A GM spokeswoman said the November 26 announcement on the plants does not violate its agreement with the union.
"We continue to work with the UAW on solutions to our business challenges," she said.
GM has said it will honoring its agreement to workers by offering affected staff positions at other plants.
Of 2,800 US hourly employees affected by the reorganization, 1,200 were eligible to retire, the company said earlier this month.
Nearly 950 workers from locations in Michigan and Ohio have accepted transfer opportunities to other GM locations in the United States, the company added.
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