WASHINGTON — President Donald Trump and his administration have rescinded an Obama-era scientific finding on climate change that has served for nearly two decades as the legal underpinning for federal regulations targeting man-made greenhouse gases.

The Feb. 12 repeal of the Environmental Protection Agency's "endangerment finding" delivers a major blow to federal efforts in the United States to address a global problem. It means greenhouse gases emitted from tailpipes on vehicles are no longer subject to regulations from the federal government.

Trump hailed the action at a White House event, calling it “the single largest deregulatory action in American history."

“That’s a big statement – in American history. I think we can add the words ‘by far,'” the Republican president added, citing White House projections that the action will reduce deregulatory costs by $1.3 trillion by reducing the cost of vehicles.

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