Editor's note: An earlier version of this story included an incorrect affiliation for consultant Yale Zhang.
BEIJING (Reuters) -- China imposed long-debated stringent fuel economy standards on Wednesday, making life tougher for cash-strapped small domestic brands that are already struggling amid a slowdown of the world's biggest auto market.
The rules, jointly issued by five government bodies including the National Development and Reform Commission, would cut passenger cars' average fuel consumption to 6.9 liters per 100 kilometers (about 34 mpg) by 2015 and down further to 5.0 liters (47 mpg) by 2020.
"That's going to be tough for everyone, especially those small players as they will have to use more fuel-efficient engines and invest in hybrid technologies," said Yale Zhang, head of Shanghai-based industry consultancy Automotive Foresight.
The latest data on passenger car fuel consumption in China was not immediately available. It stood at 7.8 liters per 100 kilometers in 2009 and 8.2 liters in 2008, said John Zeng, Asia Pacific director of consultancy LMC Automotive.
The new rules come at a time when environmental complaints have sparked unrest and even riots in some parts of the country.
Chinese Premier Li Keqiang pledged on Sunday that his government would show even greater resolve in tackling China's pollution crisis.