White House to detail rollback of US fuel economy rules as Trump targets "EV mandate"

US President Donald Trump has said he is rolling back fuel economy standards adopted by his predecessor, declaring that new rules will lower vehicle prices and encourage carmakers to expand US production. The announcement came in a social media post on Saturday, but the administration stopped short of spelling out what the replacement standards would require.

In the post, Trump said the new standards would "TERMINATE" what he called the Biden administration's "EV (electric vehicle) mandate", a label his administration and fellow Republicans have repeatedly applied to the fuel efficiency rules finalised in 2024. He accused the previous Democratic administration of burdening carmakers with costly requirements and steering American consumers towards electric vehicles.

"These new Standards will take the waste out of building cars in America. That means LOWER PRICES, saving families thousands on a new, beautiful, and safe car," Trump wrote, framing the rollback purely as an economic measure for consumers rather than an environmental or industrial policy shift.

The specifics of the rollback remained unclear at the time of writing. Trump did not provide details on the new fuel economy standards. The closest indication of where the rules may land came in December 2025, when the president announced a proposal that would set the industry-wide fleetwide average for light-duty vehicles at roughly 34.5 miles per gallon (mpg) by 2031 — a target more than 30 percent lower than the outgoing requirement.

That December proposal now appears to be the template for the standards announced over the weekend. Reposting Trump's message, US Transportation Secretary Sean Duffy said a formal announcement would be "COMING MONDAY", signalling that the complete rule text and compliance timetable will be laid out early in the week. Al Jazeera had reached out to the White House for comment on the timing and content of the announcement.

The rules at the centre of the dispute are the Corporate Average Fuel Economy (CAFE) standards, a system established by the US Congress in 1975. Under CAFE, automakers are not required to make any individual model efficient. Instead, each manufacturer must meet an average fuel economy target across all the cars and light trucks it sells, meaning a brand that markets an inefficient vehicle must offset that with a more efficient one to remain in compliance with the government standard.

The Biden administration finalised its rules in 2024, requiring the required fleetwide fuel economy to rise from 39.1mpg to about 50.4mpg by 2031. At the time, that administration said the measures would cut fuel consumption and emissions to help combat climate change while also saving motorists money at the pump — an argument that efficiency gains would more than offset any increase in sticker prices.

That trajectory had a visible effect on the industry. Auto manufacturers ramped up production of electric vehicles in order to meet the tougher Biden-era requirements, committing billions of dollars to new models, battery plants and assembly capacity aimed at the US market.

The political groundwork for reversing that shift was laid last year, when the Republican-controlled Congress gutted consumer tax incentives for electric vehicles as part of Trump's One Big Beautiful Bill Act. Removing the purchase subsidy, alongside the rollback of efficiency targets, effectively dismantles both halves of the previous administration's electric vehicle strategy.

Controversy over the phrase "EV mandate" runs through the debate. While Trump and US Republicans frequently use that term to describe the higher fuel efficiency requirements, there are no federal guidelines or laws requiring Americans to buy electric cars, nor any that prohibit the sale of petrol-powered vehicles. The dispute is therefore less about what the rules compel consumers to purchase than about who bears the cost of meeting them and what it means for the pace of an industry-wide transition.

The change also widens the distance between Washington and the direction of the global automotive market, which continues to favour electric vehicles. The rollback is part of a broader Trump administration effort to reverse Biden-era policies supporting lower-emission vehicles, setting the US apart from peers that retain or tighten efficiency requirements.

A further wrinkle surrounds the legal standing of the standards. The US transport department previously said the Biden fuel economy rules exceeded legal authority, a finding that critics of the rules cited as grounds for reconsideration and which helps explain why the administration moved to rewrite the targets rather than simply defend them.

Industry groups, consumer advocates and environmental organisations are likely to dissect the final numbers closely. A target near 34.5mpg would represent the sharpest federal downgrade in three decades, and questions about compliance credits, penalties for non-compliance and the fate of states that adopt their own standards under the waiver structure will shape how quickly the change takes effect.

For now, the immediate focus is Monday. With Duffy promising details and the president's post offering a target but no mechanics, the coming announcement will determine whether the rollback is a modest recalibration of annual efficiency increases or the full-scale reversal of the 2024 rules.