The US administration Tuesday proposed a stepped-up schedule for improving automobile fuel efficiency, accelerating plans in a law enacted last year.
Transportation Secretary Mary Peters said the new proposal would increase fuel efficiency for both passenger vehicles and light trucks by 4.5 percent per year over the five-year period ending in 2015.
This would be a 25 percent total improvement that exceeds the 3.3 percent baseline proposed by Congress last year.
"This proposal is historically ambitious, yet achievable," Peters said. "It will help us all breathe a little easier by reducing tailpipe emissions, cutting fuel consumption and making driving a little more affordable."
For passenger cars, the proposal would increase fuel economy from the current 27.5 miles (44 kilometers) per gallon (3.8 liters) to 35.7 miles (57.4 kilometers) per gallon by 2015.
For light trucks, the proposal calls for increases from 23.5 miles per gallon in 2010 to 28.6 miles per gallon in 2015.
A bill signed last year by President George W. Bush requires similar standards by 2020.
Peters said the new proposal will save nearly 55 billion gallons of fuel and a reduction in carbon dioxide emissions estimated at 521 million metric tonnes.
