(Bloomberg) -- Ford Motor Co. was blasted by its largest labor union for halting construction on a $3.5 billion battery plant in Michigan amid scrutiny of its ties to a Chinese battery maker by Republican lawmakers.

The proposed plant near Marshall, Michigan, is expected to employ 2,500 workers and produce enough batteries to power 400,000 electric vehicles a year. But Ford’s decision earlier Monday puts the facility — and its jobs — in limbo. 

“This is a shameful, barely-veiled threat by Ford to cut jobs,” United Auto Workers President Shawn Fain said in a post Monday on X, formerly known as Twitter. “Closing 65 plants over the last 20 years wasn’t enough for the Big Three, now they want to threaten us with closing plants that aren’t even open yet.”

The union, which represents 57,000 hourly Ford workers in the US, is on strike against the automaker and its crosstown rivals, General Motors Co. and Stellantis NV. Earlier Monday, the UAW said talks with Ford were “very active.” The union spared the automaker on Sept. 22 when it walked out of 38 additional GM and Stellantis plants.

But now Fain said he sees Ford’s unexpected move to pull the plug on its battery plant as “doubling down on their race to the bottom.” 

The plant was to have licensed technology from China’s Contemporary Amperex Technology Co. Ltd., which some lawmakers accused of being affiliated with the Chinese Communist Party. 

“We’re pausing work and limiting spending on construction on the Marshall project until we’re confident about our ability to competitively operate the plant,” said T.R. Reid, a Ford spokesman. “We haven’t made any final decisions about the plant investment there.”

Ford said there are “a variety of considerations” about the plant but declined to say whether the political controversy surrounding it or the current strike from the UAW had anything to do with its decision.

Ford is throttling back on ambitious electric vehicle production plans as sales growth slows due to consumer resistance to the high price of battery-powered models. Chief Executive Officer Jim Farley now says the company is aiming to quadruple sales of gasoline-electric hybrid models over the next five years.

The Detroit News earlier reported the pause in the plant’s construction.

(Updates from first paragraph with UAW reaction.)

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