BEIJING (REUTERS) - China plans to roll out the use of ethanol in petrol nationally by 2020, state media reported on Wednesday (Sept 13) citing a government document, as Beijing intensifies its push to boost industrial demand for corn and clean up choking smog.

It is the first time the government has set a targeted timeline for pushing the biofuel, known as E10 and containing 10 per cent corn, across the world's largest car market.

A renewed effort to promote biofuels will be a further blow to major oil producers.

Last Saturday, the government said it has begun studying when to ban the production and sale of cars using traditional fuels.

The news comes after the government said it would aim to double ethanol output by 2020 amid growing pressure to whittle down mountains of ageing corn in state warehouses.

The report on Wednesday said the government also aims to have large-scale domestic production of cellulosic biofuels, which are made from sources such as grasses, trees and crop waste, by 2025.

China is currently the world's third-largest ethanol producer, but with output of about 2.1 million tonnes a year, production is a long way behind global leaders Brazil and the Un States.