The repeal is an aggressive escalation in the administration's efforts both to deny climate change's impacts and to remove environmental regulations that it says will hold back the U.S. economy.
"Under the process just completed by the EPA [Environmental Protection Agency], we are officially terminating the so-called 'endangerment finding,' a disastrous Obama-era policy that severely damaged the American auto industry and massively drove up prices for American consumers," Trump said during White House remarks.
"Effective immediately, we are repealing the ridiculous endangerment finding and terminating all additional green emission standards imposed unnecessarily on vehicle models and engines between 2012 and 2027 and beyond," he added.
While the first Trump administration weakened vehicle emissions standards, Thursday's action gets rid of them entirely — meaning automakers will be under no federal obligation to reduce their climate impacts.
The first Trump administration also did not go after the now-repealed finding that greenhouse gases pose a threat to public health.
The endangerment finding has legal significance, unpinning the nation's climate change regulations.
The Clean Air Act requires the EPA administrator to regulate motor vehicle emissions of any pollutant that "in his judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare."
The Supreme Court ruled in 2007 that planet-warming emissions fall under the law's definition of air pollutants and should be regulated if they're found to be a threat to public health.
In 2009, the Obama administration determined that they do, in fact, pose a threat, setting up the EPA's authority to curb climate pollution.
At the time, the Obama administration based its finding on a determination that "increases in ambient ozone are expected to occur over broad areas of the country, and they are expected to increase serious adverse health effects in large population areas."
It also cited "the impact on mortality and morbidity associated with increases in average temperatures, which increase the likelihood of heat waves" and "the evidence concerning how human-induced climate change may alter extreme weather events."
Asked at the White House event what he would say to Americans who are concerned about the costs of his action to public health and the environment, Trump said he would tell them, "Don't worry about it, because it has nothing to do with public health. This was all a scam, a giant scam."
In a post on X, former President Obama condemned Trump's move.
"Today, the Trump administration repealed the endangerment finding: the ruling that served as the basis for limits on tailpipe emissions and power plant rules. Without it, we'll be less safe, less healthy and less able to fight climate change — all so the fossil fuel industry can make even more money," Obama wrote.
Read at TheHill.com.