Toyota and Honda aren’t keen on EV tax credits that would only be available to consumers for vehicles assembled in unionized U.S. factories.

The Clean Energy for America Act is currently under deliberation in Congress after being advanced by the Senate Finance Committee in May. It includes a provision led by Democratic Senator Debbie Stabenow of Michigan that would make EVs assembled at union sites eligible for up to $12,500 in tax credits, Auto News reports.

President Joe Biden referred to Senator Stabenow’s proposal last week, stating that the EV tax credit could consist of a “$7,500 basic credit, $2,500 credit for vehicles made in America, and an additional $2,500 credit for union-made vehicles.”

Read Also: The Nissan Leaf Is Now Up To $6500 Cheaper, But Is That Enough To Make You Buy One?

In a statement issued late last week, Honda said the proposal was unfair and discriminatory.

“Our production associates in Alabama, Georgia, Indiana, and Ohio deserve fair treatment from Congress and should not be penalized for their choice of a workplace,” Honda’s vice president and business unit leader of corporate affairs, Jennifer Thomas, said. “By providing fair and equitable treatment for all American auto workers who build EVs and by equally valuing their contributions, we can accelerate our shared environmental goal of achieving widespread EV deployment.”

Toyota’s group vice president of government affairs Stephan Ciccone echoed the sentiments of Thomas.

“This policy would unfairly discriminate against American autoworkers based on their choice of whether to unionize,” Cinnone said. “Toyota employees have already sent nearly 10,000 letters to members of Congress who represent them saying: ‘As an American, a taxpayer and a constituent, I ask you to stand up for me and my family and opposite this discriminatory proposal.’”