Supplies of natural gas could last more than 250 years if Asian and European economies follow the U.S. unconventional reserves, the IEA said.
The abundance of shale gas and other forms of so-called unconventional gas discovered in the United States prompted a global rush to explore for the new resource.
The International Energy Agency said Australia is taking the lead in the push toward unconventional gas, though China, India and Indonesia are close behind. European companies are taking preliminary steps to unlock unconventional gas as are other regions.