Nation tipped to be largest oil importer

China is expected to overtake the United States to become the world's largest oil importer in the 2020s as emerging economies, instead of developed ones, will claim most of the world's energy supplies, a report says.

China will be the main contributor to the increase in global energy use before 2020, and after then will be replaced by India as the world's biggest driving force for energy demand, the document says.

The Paris-based International Energy Agency report was released in Beijing on Wednesday.