Saving energy and increasing reductions in auto exhaust emissions are the biggest challenges facing today's auto industry, an expert and former senior Chinese government official said Thursday.

As the world's largest auto market, China must shoulder more responsibilities in these areas, as well as improve the development of renewable energies to maintain the harmonious development between society and environment,said He Guangyuan, former chief of the then-Ministry of Machine Industry.

"How to maintain sustainable development of the auto industry from a technological perspective is an issue for thinking and deep discussions," He said, as explosive growth of the auto sector is putting pressure on both the environment and the nation's energy industries.

He made his remarks at an industrial forum held Thursday in Changchun, capital of northeast China's Jilin Province.

China became the world's largest auto market as it sold more than 13 million vehicles last year, and the market kept rapidly expanding as sales in the first half of 2010 jumped almost 48 percent year on year to 9.02 million units.

The Chinese government is now studying plans for the promotion of new energy-efficient autos as "a five-year or ten-year plan is expected to be rolled out in the third quarter of this year," said Dong Yang, Secretary General of the China Association of Automobile Manufacturers.

The government announced in June that it would subsidize the purchase of green cars in a bid to reduce vehicle emissions. Further, subsidies of up to 60,000 yuan (8,784 U.S. dollars) will be provided to buyers of completely electric vehicles in the five pilot cities of Shanghai, Changchun, Shenzhen, Hangzhou and Hefei.