US President Barack Obama on Tuesday ordered officials to start setting new fuel efficiency standards for medium and heavy trucks, wielding his executive power in the fight against climate change. Such vehicles account for just four percent of traffic yet make up 25 percent of fuel use and greenhouse gas emissions in road transportation, the White House said. Obama says that introducing new fuel standards, as he has already done for cars and light trucks, creates American jobs in innovation, saves drivers money and is good for the economy and the environment. "We're creating jobs. We're generating more clean energy. We're cutting our dependence on foreign oil," Obama said at a supermarket distribution center outside Washington. "We're pumping out less dangerous carbon pollution. If we keep going down this road, then we're going to have a future full of good-paying jobs." Obama directed the Environmental Protection Agency and the National Highway Traffic Safety Administration (NHTSA) to issue new medium- and heavy-duty vehicle fuel efficiency standards by March 31, 2016. Obama said a first round of new fuel efficiency standards for such models, finalized in 2011, was projected to save 530 million barrels of oil and reduce greenhouse gas emissions by approximately 270 million metric tons. He said it will save vehicle owners and operators an estimated $50 billion in fuel costs over the lifetimes of their vehicles. Tuesday's event represented another attempt by the president to show that, even as much of his agenda is blocked by Congress, he plans to use executive power to maximize his capacity to carry out political change in his second term. As part of his climate change and green energy agenda, the president has also introduced new fuel efficiency standards for cars and light trucks. The administration says the requirements, spanning model years 2011 through 2025, double fuel economy in the average vehicle, cut emissions by 6 billion metric tons and will save customers $1.7 trillion at the pump.