WASHINGTON (AFP) - US regulators announced on Friday stricter rules on vehicle emissions and low-sulfur gasoline as part of President Barack Obama's efforts to reduce pollution.
The Environmental Protection Agency's (EPA) new proposed rules will require ultra-low sulfur gasoline as well as stricter tailpipe emissions standards for cars and light trucks.
"The proposed standards will reduce gasoline sulfur levels by more than 60 per cent - down to 10 parts per million (ppm) in 2017," the EPA said in a statement.
"The proposal is designed to be implemented over the same timeframe as the next phase of EPA's national programme to reduce greenhouse gas (GHG) emissions from cars and light trucks beginning in model year 2017."
The Obama administration has said the proposal would result in a one cent per gallon cost increase at the gas pump.
But critics say the costs will be higher, with industry estimates ranging from six to nine cents more per gallon.
"With US$4 dollar a gallon gas the norm in many parts of the country, we cannot afford policies that knowingly raise gas prices," said House Energy and Commerce Committee Chairman Fred Upton, a Republican from Michigan.
A massive lobbying effort by oil and gas interests to delay the rules was unsuccessful, according to US media reports.
High sulfur content in gasoline creates more pollutants and adds to smog and soot in the air.
Supporters of the new rules hailed the move as a crucial step in Mr Obama's second term as US president.
The new standards could be "the most significant air pollution policy President Obama will adopt in his second term," Mr S. William Becker, executive director of the National Association of Clean Air Agencies, was quoted as telling the Washington Post.
"There is not another air pollution control strategy that we know of that will produce as substantial, cost-effective and expeditious emissions reductions."
The proposed standards are to be published in the Federal Register, after which there will be a period of public comment.