That assessment followed a 2007 U.S. Supreme Court decision in its landmark Massachusetts v. EPA case that said the EPA has the authority under the Clean Air Act to regulate greenhouse gas emissions and required the agency to make a scientific finding on whether those emissions endanger public health.

The long-expected move comes after Republicans recently disarmed fuel economy standards and canceled influential state-level emissions rules.

The Trump administration’s U.S. Environmental Protection Agency proposed on Tuesday revoking a science-based determination that pollution fueling climate change harms public health. The