Earth lacks the water, energy and agricultural land to allow China and India to attain Western living standards, a US think-tank has warned.
China's economy could outstrip Earth's resources
The Worldwatch Institute said the booming economies of China and India are "planetary powers that are shaping the global biosphere".
Its State of the World 2006 report said the two countries' high economic growth hid a reality of severe pollution.
It said the planet's resources could not keep pace with such growth.
"The world's ecological capacity is simply insufficient to satisfy the ambitions of China, India, Japan, Europe and the United States as well as the aspirations of the rest of the world in a sustainable way," the report added.
It said that if China and India were to consume as much resources per capita as Japan in 2030 "together they would require a full planet Earth to meet their needs", it said.
The institute's report said that in the next few years the choices China and India made could lead to political and economic instability, or they could usher in an age of better stewardship of resources and more efficient technology.
The reports said the US - which continues to consume more of the Earth's resources than any other country - needed to cooperate with China and India to help develop more environmentally friendly practices and technologies.
"China and India are positioned to leapfrog today's industrial powers and become world leaders in sustainable energy and agriculture within a decade," Worldwatch Institute president Christopher Flavin said.
"We were encouraged to find that a growing number of opinion leaders in China and India now recognise that the resource-intensive model for economic growth can't work in the 21st Century," he said.
China already has a solar-powered heating system which supplies hot water to 35 million homes, while India has pioneered a system bringing clean water from rainfall, the report said.