The global demand for energy is set to grow inexorably through to 2030 if governments do not change their policies, warns a top energy official.
The world is becoming increasingly energy intensive
Nobuo Tanaka, executive director of the International Energy Agency (IEA), said such a rise would threaten energy security and accelerate climate change.
He said energy needs in 2030 could be more than 50% above current levels, with fossil fuels still dominant.
Mr Tanaka was speaking at the launch of the IEA's World Energy Outlook report.
Rapid economic growth in China and India would be the main drivers behind the rise, he said as he unveiled the agency's annual flagship publication.
"The emergence of new major players in global energy markets means that all countries must take vigorous, immediate and collective action to curb runaway energy demand," he warned.
"Rapid economic development will undoubtedly continue to drive up energy demand in China and India, and will contribute to a real improvement in the quality of life for more than two billion people.
"This is a legitimate aspiration that needs to be accommodated and supported by the rest of the world."
The World Energy Outlook 2007 report warned that much of the increased demand for energy would be met by coal.
As a result, energy-related carbon dioxide (CO2) emissions could rise by 57% - from 27 giga-tonnes in 2005 to 42 giga-tonnes in 2030, it said.
Even in the report's "alternative policy scenario", which takes into account the governments' proposed action to save energy and cut emissions, CO2 levels are set to rise by 25%.
But it offered a glimmer of hope within its "450 Stabilisation" case study.
It described a notional strategy for governments to stabilise CO2 levels in the atmosphere at about 450 parts per million (ppm), which some scientists and policy makers suggest is an acceptable concentration.
"Emissions savings come from improved efficiency in industry, buildings and transport, switching to nuclear power and renewables, and the widespread deployment of carbon capture and storage," the report said.
This approach would see global emissions peak in 2012 then fall sharply below 2005 levels by 2030, it suggested.
But it added: "Exceptionally quick and vigourous policy action by all countries, and unprecedented technological advances, entailing substantial costs, would be needed to make this case a reality."
Mr Tanaka stressed the need for urgency in the battle against climate change: "We need to act now to bring about a radical shift in investment in favour of cleaner, more efficient and more secure energy technologies."
The UK's Energy Secretary, John Hutton, endorsed the IEA's findings and agreed that urgent action by politicians was needed.
"As the IEA states, it is a lack of international political will, not technological innovation, that is preventing us from reducing emissions while securing energy supplies to power our homes and businesses for the years ahead," he told BBC News.
"The UK must continue to lead by example by embracing innovation while also ensuring it takes advantage of existing low carbon technologies.
"We share view that there should be the broadest possible energy mix and will be carefully examining the recommendations of this report as we prepare to introduce our Energy Bill."