The U.S. government has a deal with 13 automakers to increase fuel efficiency to 54.5 miles per gallon (4.3 L/100 km) for cars and light-duty trucks by 2025, President Barack Obama announced Friday.

That is about double the 27 miles per gallon (8.7 L/100 km) average that cars get now, and builds on a 2009 deal with the auto companies that will see cars and trucks averaging 35.5 mpg (6.6 L/100 km) by 2016.

The greater fuel efficiency is likely to push up the price of new vehicles, but the actual increase will not be known until the regulations are written, starting in September.

Buyers of new vehicles will actually get closer to 40 mpg (5.9 L/100 km) because manufacturers will get credit for electric and alternative-fuel vehicles.

Obama was enthusiastic about the deal.

"This agreement on fuel standards represents the single most important step we’ve ever taken as a nation to reduce our dependence on foreign oil," Obama said at a Washington meeting with auto industry executives representing 90 per cent of the U.S. car market.. The United Auto Workers union and California, which has been pressing for higher standards, were also represented.

He said the new standard will also reduce consumers' driving costs and cut greenhouse-gas emissions.

"It means filling up your car every two weeks instead of filling it up every week," he said.

The deal was a compromise between environmentalists and the carmakers.