Tough new U.S. rules governing greenhouse gas (GHG) emissions from large trucks and buses edged forward last week when the Environmental Protection Agency (EPA) sent draft proposals to the White House.

The agency has been working with the U.S. Department of Transportation (DOT) since May to craft improved emissions standards after President Barack Obama announced that he wanted new rules to come into effect for medium and heavy-duty trucks between 2014 and 2018.

The White House said at the time that it was confident haulage firms could cut emissions from heavy trucks by about 20 percent using existing technologies.

Now the EPA and DOT have lodged draft standards with the White House Office of Management and Budget (OMB) for review.

The OMB provided no details on the nature of the proposed rules, signaling only that it has received a draft proposal for "commercial medium- and heavy-duty on-highway vehicles and work truck fuel efficiency standards."

However, the move suggests the administration remains on track to meet its target of finalizing the new regulation by July of next year.

"This action would set national emission standards under the Clean Air Act to control greenhouse gas emissions from heavy-duty trucks and buses," the OMB explained in a brief statement on its website. "This rulemaking would significantly reduce GHG emissions from future heavy-duty vehicles by setting GHG standards that would lead to the introduction of GHG-reducing vehicle and engine technologies."

The proposed standards are part of a wider campaign from the Obama administration to curb emissions from vehicles, which saw the White House introduce tough new emissions standards covering cars and light vans earlier this year that are expected to cut carbon emissions from new vehicles by 30 percent by 2016.

This article originally appeared at BusinessGreen.com and is reprinted with permission.

Image CC licensed by Flickr user MrAnathema.