While America's 4 percent increase in food prices last year seems modest compared to the situation in some foreign countries, it represents the largest domestic price hike in 17 years.
Senior Bush Administration officials defended corn-based ethanol this week, calling it "a factor in rising food prices," but placing most of the blame directly on higher energy costs.
The White House long has championed ethanol's role in reducing America's dependence on foreign oil, and this week the president included biofuels in his revised policy on climate change.
For the first time, the president set a specific date for U.S. climate pollution reductions and said he was ready to commit to a binding international agreement on long-term cutbacks as long as other countries such as China do the same.
Bush said he envisions a "comprehensive blend of market incentives and regulations" that would encourage clean and efficient energy technologies. But he singled out the electric utility industry, saying power plants need to stabilize carbon dioxide pollution within 15 years and reduce them thereafter.
The White House characterized the move as a fresh strategy to attack climate change, but the president gave no specific proposals for achieving the pollution reductions. Instead, Bush cited measures already enacted, including a 40 percent increase in auto fuel economy standards and expanded use of ethanol and other biofuels.
The plan was immediately criticized by environmentalists and congressional Democrats who favor mandatory emission cuts.
Environmentalists said the Energy Department's own forecasts have shown that even with recent advances — encompassed in energy legislation approved last year — U.S. carbon dioxide emissions are expected to increase roughly 10 percent by 2025.
The U.S. Senate is expected to consider legislation in June mandating nearly a 20 percent cut in greenhouse gas emissions by 2025. The Senate proposal could call for a 70 percent reduction from power plants, transportation and industrial sources by 2050.
Bush called those requirements "unrealistic" and economically damaging. But he prefers some congressional action on climate change this year to avert what aides have characterized as a "train wreck" of regulations under existing laws such as the Clean Air Act and Endangered Species Act.
Last year, the Supreme Court declared that carbon dioxide is a pollutant under the Clean Air Act and directed the Environmental Protection Agency to determine whether CO2 is endangering public health or welfare. If so, the court said, the EPA must regulate CO2 emissions.