Carmaking heavyweights General Motors, Toyota and Fiat Chrysler have backed President Donald Trump's efforts to ban California from maintaining its own stricter standards on car emissions, the auto giants have confirmed. The announcement is the latest salvo in a months-long battle over car pollution between the White House and the US state, whose Democratic leaders have made fighting climate change a priority. California -- which has some of the most polluted cities in the country -- has used tough emissions standards to improve air quality and become a model for green tech.
But Washington stripped the state of its decades-old right to set its own car pollution regulations in September, arguing that higher standards depressed the new car market and kept older and more unsafe vehicles on the road.
California responded by suing the Trump administration to block the move, alongside nearly two dozen other US states.
The three automakers announced that they would support Washington in that legal action.
"With our industry facing the possibility of multiple, overlapping and inconsistent standards that drive up costs and penalize consumers, we had an obligation to intervene," said John Bozzella, a spokesman for a coalition representing the firms.
The move exposes a split in the industry, putting the trio of manufacturers at odds against other leading auto companies that have backed California's tougher regulations.
The state reached a deal with four major carmakers in July to produce more fuel-efficient cars for the American market.
The automakers pledged to make increasingly efficient vehicles that can average 50 miles per gallon by 2025.
But the White House was infuriated by the agreement, instructing the Department of Justice launch an antitrust investigation against Ford, Volkswagen, Honda and BMW in response.
At that time, Trump also reportedly summoned other carmakers to the White House to warn them against agreeing to a similar deal.