President Barack Obama will propose a significant increase in US auto fuel efficiency on Tuesday, which includes directly regulating emissions for the first time and addressing a dispute with California over cleaner cars. The proposal would raise average fuel standards for all new passenger vehicles by 10 miles per gallon to 35.5 miles per gallon between 2012-16, resulting in a 30% decrease in climate-warming carbon emissions. The initiative is expected to save 1.8 billion barrels of oil and require all companies to produce more efficient and cleaner cars. Major US and overseas automakers, such as General Motors Corp and Toyota Motor Corp, support the plan. GM's CEO Fritz Henderson believes that having more consistency and certainty in regulations will benefit both GM and the auto industry. Toyota's President James Lentz also supports the idea of a single national standard, stating that it will provide consumers with more vehicle choices. The new program, which will increase the cost of producing a vehicle by about $600 compared to current regulations, aims to achieve a fleet average of 35 mpg by 2020. US auto companies have resisted fuel efficiency standards for many years, but tighter targets were agreed upon in 2007. Some vehicles, particularly those made by overseas manufacturers, already meet or exceed the proposed standards. California previously wanted to have its own regulations for reducing auto emissions, but the Bush administration did not allow it. Auto companies also opposed this idea, fearing it would lead to different rules in different states. Now, California has agreed to follow the national standard proposed by Obama. Senator Barbara Boxer sees this as a positive step towards reducing global warming and decreasing America's reliance on foreign oil. The 30 percent decrease in emissions is more ambitious than what California and other supportive states have requested. In April, the administration shifted policies by recognizing climate-warming pollution as a threat to human health and welfare, allowing for the regulation of emissions. This new approach would allow automakers flexibility in meeting standards and consider the environmental impact of carbon-based fuels and emissions from other vehicle systems. David Friedman, research director at the Union of Concerned Scientists, believes this could be a significant step forward in promoting clean cars. The plan is based on an assumption of average gas prices reaching $3.50 per gallon by 2016, which officials hope will encourage consumers to choose more fuel-efficient vehicles. Automakers are actively working on improving hybrid and electric cars, but recent drops in gas prices have led to an increase in sales of less efficient pickups and SUVs. To boost the industry, Congress is discussing a proposal to give consumers up to $4,500 to trade in older, less fuel-efficient vehicles for ones with better gas mileage. Additionally, a US congressional committee started a week-long debate on climate change, with Democrats pushing for a bill to combat global warming and Republicans opposing a key aspect of the plan.