Halving greenhouse gases with clean energy schemes will cost $45 trillion by 2050
A leading energy body is calling for a $45 trillion (£23 trillion) green revolution to tackle global warming.
The International Energy Agency (IEA) said nations must spend 1% of annual economic output on new technology to halve carbon dioxide emissions by 2050.
It warned that without action, CO2 emissions would rise by 130% and oil demand would jump by 70% by the middle of the century.
But the IEA added that meeting the new target would be a formidable challenge.
"We would require immediate policy action and technological transition on a unprecedented scale," the IEA's executive director Nobuo Tanaka said.
"It would essentially require a new global technological revolution which would completely transform the way we produce and use energy."
The agency called for increased use of carbon dioxide capture and storage techniques, renewable and nuclear power and better energy efficiency.
The IEA report comes ahead of a meeting of energy ministers from the G8 group of leading industrialised nations in Japan this weekend.
They will be debating clean energy targets as oil prices continue to rise. The price of light sweet crude jumped $6 to more than $134 a barrel on Friday.
Just last month, G8 environment ministers called for a global target to halve greenhouse gas emissions by 2050.