Instead, standards would be frozen at the 2020 level until 2026.
"Engines would run smoother", Trump continued.
US President Donald Trump on Wednesday attacked automakers who ignored his advances and instead reached an agreement with California on future stricter emissions standards.
Ford is one of four automakers, along with Honda Motor Co, BMW AG and Volkswagen AG, that reached a voluntary agreement with California on fuel efficiency rules, defying Trump and his administration's effort to strip the state of the right to fight climate change by setting its own standards.
The rules under the California plan are looser than the Obama-era regulations but stricter than what the Trump has proposed.
And he accused California of wanting to "squeeze them to a point of business ruin".
"About a quarter of that mandate could be offset by credits for adopting cleaner technologies in the vehicle design, such as improved internal temperature controls, and by selling more electric or hybrid cars", he wrote.
Even so, Trump tweeted that the founders of Ford and GM "are "rolling over" at the weakness of current auto company executives" over the fuel rules, adding: "Crazy!"
The companies also want to avoid a split market - with federal mileage requirements in most states and more stringent rules in more than a dozen states that adhere to California's standards.
"Ensuring that America's vehicles are efficient, safe and affordable is a priority for us all", automakers said in a July statement.
"The Legendary Henry Ford and Alfred P. Sloan, the Founders of Ford Motor Company and General Motors, are "rolling over" at the weakness of current auto company executives willing to spend more money on a vehicle that is not as safe or good, and cost $3,000 more to consumers", Trump said later Wednesday in another tweet. The proposal said that by the 2030 model year, the average price increase of a new vehicle would be reduced by US$1,850 and consumers would pay US$490 less for financing, insurance and taxes.
Sources tell the Times that Mercedes-Benz is also expected to agree to meeting the state's emissions rules, but the automaker hasn't yet confirmed that it will do so. The Trump administration say their preferences would keep cars both safer and less expensive to manufacture.
The administration is preparing to issue the biggest single deregulatory rule of Mr. Trump's presidency, creating one federal standard for fuel economy and rescinding a 2012 Obama administration rule that required automakers to raise the average mileage standard of new cars and trucks to 54.5 miles per gallon by 2025.
Hamilton lands three new stores in pot-shop lottery
The Garden City is already home to Niagara's first retail cannabis store, The Niagara Herbalist at 33 Lakeshore Rd., Unit 15. The location of the proposed pot shop is also being supported by the Downtown Windsor Business Improvement Association.