President Donald Trump moved to freeze future vehicle emission targets Wednesday, during a trip to the faded US automotive hub in Michigan.
Insisting higher environmental standards hurt trade, Trump announced that targets for 2022-2025 will be put on hold pending review.
"We're going to help the companies, and they're going to help you," Trump said after touring an automotive testing facility near Detroit.
"I'm asking all of the companies here today to join us in this new industrial revolution."
The Trump White House says the rules were issued in an 11th hour move by the Obama administration without taking into consideration the realities of the market, the constraints of various actors in the field and consumer expectations.
But White House officials also admit they have not examined what impact the move may have on exports.
Major markets, including 13 US states -- most notably California-- as well as Japan and European nations have their own emission standards that are often higher than US federal levels.
In a February letter to Environmental Protection Agency (EPA) Administrator Scott Pruitt, US auto manufacturers had asked the new president to suspend the Obama administration's restrictions, saying they could threaten employment.
Trump on Wednesday also told a roundtable of automotive chief executives that he would help them if the relationship ran both ways.
"We're going to do some wonderful work with you but you're going to have to help us with jobs," he said.
Since his January 20 inauguration, Trump has repeatedly indicated he wants to slash environmental regulations, saying they are hurting job creation in the United States.
Pruitt, the former attorney general of Oklahoma, was one of the EPA's fiercest opponents prior to being named by Trump to head the agency.
Last week, Pruitt sparked outrage when he went against scientific consensus in claiming that increasing greenhouse gas emissions were not a determining factor in climate change.