The United Auto Workers (UAW) union has accused GM’s battery-making joint venture, Ultium Cells, of denying it access to workers to conduct a preliminary organizing vote.

The UAW’s vice president, Terry Dittes, wrote in a letter to union leaders that the joint venture between GM and LG Energy has “flat out rejected” the union’s proposal of a “card check agreement” to organize, reports CNBC, which obtained a copy of the letter.

The agreement would have allowed the union’s officials to enter an Ultium Cells plant in Ohio (which is not yet operational) to collect organizing cards. The move would have been a first step towards establishing its presence at the plant, a topic of some controversy there.

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“This process has been agreed to by many employers for a smooth and peaceful recognition of the UAW,” Dittes said in the letter. “Ultium flat out rejected those simple basic features of a card check recognition we proposed.”

In April 2021, former UAW President Rory Gamble expressed concerns about battery-making joint ventures that are not required to be union-represented, unlike GM’s other plants.

“We’ve got to make sure that work stays at a livable wage and those workers can organize,” Gamble said at the time. “We don’t need another service sector in this country. That’s what I am fearful of. If these jobs are low wage minimal benefit jobs it’s not going to benefit the economy.”

Although Ultium did not deny the claims made in the letter, a spokesperson did say that it supported allowing workers to choose whether or not they want to be represented by the UAW.

“The UAW has expressed interest in representing a portion of the Ultium Cells workforce and we have had initial discussions around a Neutrality Agreement that could enable a card check process at our facility in Warren, Ohio,” Ultium spokeswoman Brooke Waid said in a statement. “We are, and always have been, supportive of the process that allows our people to determine their own representation status, which is a matter of personal choice.”

General Motors and the UAW have been at odds recently, with the longest auto strike in recent memory having come to an end just before the pandemic started.

The first of three Ultium Cells plants planned for America, the Lordstown, Ohio, plant referred to above will likely have an impact on more than just the 1,100 workers it will need to operate. This plant in particular, though, is meaningful since it is next to a plant that had 1,700 union-represented workers that GM closed in 2019.

The UAW letter, meanwhile, was reported on just one day before Ford, GM’s Detroit rival, announced that it will be hiring 6,200 more union workers and providing better benefits to them.

Dittes, though, was sanguine about the union’s prospects at the Ultium Cells plant, despite this alleged setback.

“We will represent the employees there and at all the future Ultium sites currently under construction,” he wrote in the letter. “We will not be slowed down to organize workers who want to join our Union!”