WASHINGTON (NYTIMES) - Many of the world's largest automakers joined together on Thursday (June 6) to tell United States President Donald Trump that one of his most sweeping deregulatory efforts - his plan to weaken pollution standards for automobiles - threatens to hurt their profitability and produce "untenable" instability in one of the nation's most important manufacturing sectors.
In a letter signed by 17 companies including Ford, General Motors, Toyota and Volvo, the automakers asked Mr Trump to go back to the negotiating table on the planned rollback.
It represents the most forceful public rebuke to date by the auto industry of Mr Trump's push to weaken the tailpipe pollution rules, one of President Barack Obama's signature policies to fight climate change.
Mr Trump's new rule, which is expected to be unveiled in the coming weeks, would all but eliminate the Obama-era auto pollution regulations, essentially freezing mileage standards at about 37 miles per gallon (15km per litre) for cars, down from a target of 54.5 MPG by 2025.
The policy makes it a near certainty that California and 13 other states will sue the administration while continuing to enforce their own, stricter rules - in effect splitting the US auto market in two.
For automakers, a bifurcated market is their nightmare scenario. In the letter to Mr Trump, a copy of which was reviewed by The New York Times, they warned of "an extended period of litigation and instability" should his plans be implemented.
The letter was delivered to the White House on Thursday morning, along with a similar letter to Governor Gavin Newsom of California, according to a senior auto industry lobbyist who was not authorised to speak about the matter because the letters had not yet been made public.
"We strongly believe the best path to preserve good auto jobs and keep new vehicles affordable for more Americans is a final rule supported by all parties - including California," the letter says.
Some officials have said that they fear auto industry criticism of Mr Trump's rollback could lead the President to retaliate by imposing tariffs on auto imports. That, too, could be painful for the industry, because many cars and components are now made or partly assembled across the border in Mexico or Canada.
The automakers conceded in their letter that they were seeking to solve a crisis of their own making. Soon after Mr Trump took office, chief executive officers from Detroit's top automakers personally asked him to loosen the some elements of the Obama-era regulations.
However, the Trump administration went further than the industry expected, using the rollback to attack California's legal authority to set its own rules.