President Trump directed the Environmental Protection Agency on Wednesday to shelve aggressive vehicle fuel economy targets that have been a foundation for battles against climate change and harmful pollution in California and across the country. The regulations to be reviewed ... had set ambitious targets for vehicle mileage. The decision puts the White House on a path toward a direct and costly confrontation with California. State officials, pointing to California's unique authority under the Clean Air Act, have made clear they will not waver from requiring passenger cars to average about 54 miles per gallon by 2025, up from an average of 36 miles per gallon today. Trump's announcement comes amid a lobbying blitz from a coalition of the world's largest vehicle makers, which complained in a letter to the new administration that the existing EPA rules place unreasonable and expensive demands on the industry. The ultimate fate of the regulations may now be decided in a legal brawl between California and the Trump administration. The state is already moving to defend the federal regulations in court. "Any weakening or delay of the national standards will result in increased harms to our natural resources, our economy, and our people," reads a legal filing submitted Tuesday by the state. Under the Clean Air Act, the state can impose emissions standards stronger than those set by the federal government, and a dozen other states have embraced the California rules.