Washington - The US government on Tuesday gave California the right to impose tough new efficiency standards on carmakers, in a landmark environmental ruling that opens the door for 13 other states to follow suit later this year. The decision by the Environmental Protection Agency marks a shift under President Barack Obama and comes after the struggling US car industry agreed last month to work towards a new set of national standards for petrol efficiency in the coming years.
Obama's national plan, designed to help reduce greenhouse-gas emissions blamed for global warming, would only apply to 2012 models at the earliest.
But some states will now get a head start: California can impose its own standards immediately. Another 13 states and the District of Columbia are in the process of adopting the same rules.
"The decision puts the law and science first," said EPA Administrator Lisa Jackson. "More importantly, this decision reinforces the historic agreement on nationwide emissions standards developed by a broad coalition of industry, government and environmental stakeholders earlier this year."
The Obama administration reached a deal with US car companies to raise petrol standards, starting with 2012 models, from 27.5 miles per gallon (8.71 litres per 100 kilometres) to 35.5 miles per gallon (6.62 l/100 km) by 2016.
The state laws dovetail with Obama's 2012 plan. The 14 states now expected to enact new efficiency requirements account for about 40 per cent of all US car sales.
The so-called "waiver" for US states ends a seven-year saga that began after California's state legislature approved the harshest efficiency levels for cars in the country, putting the state on a collision course with former president George W Bush.
California's law was challenged by US carmakers in court and the Bush administration blocked the state effort. The EPA, now under Obama, said its decision Tuesday "returns to its traditional legal interpretation" of previous air quality laws passed by Congress.
US carmakers had long been reluctant to build greener models. But Detroit's manufacturers have begun shifting gears as leaner foreign rivals have stolen market share and the recession pushed US companies to the brink of collapse.
