Richard Jones, the deputy executive director of the International Energy Agency, told delegates in London that the "most important" way to cut greenhouse gas emissions is to improve energy efficiency.
He said decarbonizing the power and transportation sector along with improving overall energy efficiency must be embraced if climate objectives are to be achieved.
"The transition to a low-carbon economy will not only tackle climate change but can also provide energy security benefits for many countries that are heavily dependent on fossil energy imports," Jones said in a statement.
Jones said the international community needed to pursue more nuclear energy, carbon capture and storage and renewable energy as part of a broad-based plan to clean up the environment.
At best, he said, the world demand for fossil fuel as a primary source of energy could fall from 81 percent of the energy mix currently to 46 percent in 2050.