SAN FRANCISCO (AP) -- A federal appeals court is allowing California to resume working on new regulations that mandate greener fuels for cars and trucks.

The U.S. 9th Circuit Court of Appeals on Monday overturned a federal judge's injunction blocking California's low-carbon fuel standard.

The appellate court's decision allows the California Air Resources Board to continue preparing the first-in-the-nation regulations while it appeals a lower-court judge's decision to halt the program.

In December, U.S. District Court Judge Lawrence O'Neill ruled that the new standard discriminates against out-of-state fuel producers.

The mandate requires all vehicles' fuels, on average, to be 10 percent less carbon-intensive by 2020 than they are now.

The standard was created as part of California's landmark global warming law requiring the state to drastically reduce its greenhouse-gas emissions.

Copyright 2012 The AP.