AOMORI, Japan - Faced with record-high oil prices, the world's leading economies and oil consumers yesterday pledged greater investment in energy efficiency and green technologies to control their spiraling thirst for petroleum.

In a joint statement, energy ministers from the Group of Eight countries, joined by China, India and South Korea, also urged oil producers to boost output, which has stalled at about 85 million barrels a day since 2005, and called for cooperation between buyers and producers.

But with little prospect for a surge in production anytime soon, the focus of yesterday's meeting was on what wealthy nations should do to rein in consumption, while reducing carbon emissions blamed for global warming.

"We also have to address, too, the demand side of the equation," said John Hutton, Britain's business secretary. "We will do that through new measures to improve energy efficiency [and] accelerate our moves to a new, low-carbon form of energy generation."

The 11 nations, which account for 65 percent of the world's energy consumption, grappled with oil prices that have hit record highs. Prices made a massive 8 percent gain Friday to $138.54 on the New York Mercantile Exchange.

Energy experts say most producers have little ability to expand output. The exception is Saudi Arabia, which is producing about 9.4 million barrels a day and could increase by about two million barrels a day, but has not done so.

The current president of the Organization of Petroleum Exporting Countries, Chakib Khelil, has said that the cartel would make no new decision on production levels until its Sept. 9 meeting in Vienna.

While the nations meeting yesterday did not pledge specific amounts of money, they said they would set goals in line with International Energy Agency (IEA) recommendations for a vast expansion of investment in renewable energies and energy efficiency.

For instance, the G-8 countries - the United States, Japan, Russia, Germany, France, Britain, Italy and Canada - pledged to launch 20 demonstration projects by 2010 on "carbon capture and storage," which would allow power plants to catch emissions and inject them into underground storage spaces.

While that technology is still in its infancy, proponents say it could eventually allow the expanded exploitation of the world's abundant supply of cheap coal without polluting the environment and speeding global warming.

There were clear rifts, however, on how to approach another technology promoted by some as an answer to oil dependence: nuclear energy.

The carefully worded joint statement called for assurances on safety and security of nuclear materials, but several nations - the United States, Canada and Britain - said they were determined to build new reactors. Japan also has ambitious nuclear goals.

The IEA, in a report issued last week, estimated the world would have to construct 32 nuclear power plants each year from now until 2050 as part of an effort to cut global greenhouse gas emissions by 50 percent.

"I don't think it's an unreasonable forecast or estimate," Energy Secretary Samuel Bodman said of the IEA study. "I think we're really on the verge of a very substantial increase in the number of nuclear power plants."