President Trump said on Wednesday the Environmental Protection Agency is formally revoking California's right to set its own stricter vehicle emissions rules, setting up a massive legal fight with high-stakes consequences for U.S. automakers and greenhouse gas emissions. The Trump administration has long signaled its intention to revoke California's special authority to set its own auto emissions standards, granted under the 1970 Clean Air Act; 13 states have pledged to follow California's stricter rules. California vowed to fight the waiver withdrawal all the way to the Supreme Court. Trump's move against California was originally supposed to be part of a broader rollback of fuel economy standards set under President Barack Obama, but it was pushed forward as the other parts of the plan hit internal roadblocks.

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