A new government forecast is calling for diesel prices to average just below the same level this year as it was in 2012 and ease further next year.

The U.S. Energy Department’s Energy Information Administration says diesel fuel prices, which averaged $3.97 per gallon in 2012, will average $3.96 per gallon in 2013 and $3.82 per gallon in 2014, in the latest Short-Term Energy Outlook.

Diesel averaged $3.88 in the second quarter of the year, but once the third quarter is wrapped up, it is expected to be higher at $3.94, the same as where it clocked in during the third quarter of 2012.

Led by falling crude oil prices, the projected U.S. average regular gasoline retail price is expected to fall from $3.63 per gallon in 2012 to an average $3.55 in 2013 and $3.43 in 2014.

Much of the reason the department says gasoline prices will move lower is it continues to expect declining gasoline consumption in 2014, as improving fuel economy of new vehicles continues to outpace growth in highway travel, while world demand for diesel is expected to grow according to other reports, with the U.S. increasingly refining more oil for diesel exports.

The department says while U.S. crude oil production increased to an average of 7.6 million barrels per day in August, the highest monthly level of production since 1989, monthly average crude oil prices increased for the fourth consecutive month in August, as supply disruptions in Libya increased and concerns over the conflict in Syria intensified. Also the total volume of world crude production that is offline because of unplanned outages among OPEC and non-OPEC producers in August was the highest since at least January 2011.

The forecast for Brent crude oil spot price, which averaged $108 per barrel during the first half of 2013, is forecast to average $109 per barrel over the second half of 2013 and $102 per barrel in 2014, $5 per barrel and $2 per barrel higher than forecast in last month's prediction, respectively.

Projected West Texas Intermediate crude oil prices should average $101 per barrel during the fourth quarter of 2013 and $96 per barrel during 2014.

Energy price forecasts are highly uncertain and could differ significantly from the projected levels, says the department.

The report assumes 1.6% real U.S. GDP growth in 2013, rising to 2.6% in 2014, while year-on-year real GDP growth begins to accelerate in the second half of 2014, eventually rising to 3.2% in the fourth quarter of 2014.