WASHINGTON — New medium- and heavy-duty trucks will have to cut fuel consumption and emissions by 10 to 20 percent under first standards announced today by the Obama administration.

For the first time, the Environmental Protection Agency and the Transportation Department say that work trucks, school buses, long haul trucks and more will need to get more miles to the gallon than they do today.

Big rig trucks will see the greatest change: They'll be required to decrease fuel consumption and emissions by 20 percent in 2018. Other vehicles will see reductions in fuel consumption and emissions of 10 to 15 percent.

The new standards were required under provisions of a 2007 energy law and will cover vehicles sold in the 2014 model year and extending to the 2018 model year.