The government's decision to encourage development using energy-saving and environmentally-friendly cars was long overdue.

For a major developing country such as China, energy supply and environmental protection have to be at the top of the list of national priorities. Fast economic growth has already tested the country's limits in both regards.

Automobiles currently guzzle more than three-fifths of China's total petrol output and one-fifth of diesel production. The number of cars on the roads, especially in major cities, has been rising exponentially over the past few years.

Reining in the impact on the energy supply and environment as the country becomes a society on wheels is crucial to sustainable social and economic development.

The recent notice issued by the government has made the country's automobile industrial policy look greener than ever.

But to drive home the idea of eco-friendly motoring when most of the population is only just beginning to contemplate the automobile dream is no easy task.

A particular obstacle in this country is local officials' discrimination against the use of small cars.

Blanket bans have been imposed on the use of small cars with low engine displacement in many domestic cities for years. Some claim such cars add to traffic jams because of their low mobility. Others simply insist small cars are not good for the image of a city.

Such discrimination simply based on engine displacement is neither technologically justified nor desirable for industrial development. But it does reflect the fact that most small cars on Chinese roads are synonymous with low-level technology and poor quality.

Technological progress has largely changed this impression. With more efficient engines and the use of alternative energy sources, small cars have increasingly demonstrated huge potential in automobile markets at home and abroad.

The government's decision to put a stop to those outdated bans on the use of small cars by the end of March is a welcome step.

Nevertheless, while applauding the about-face in policy-makers' attitudes towards cars with low engine displacement, a resurgence of small and poor quality vehicles should not be encouraged.

By interpreting the government notice as an effort to lift the ban on small cars, many domestic media outlets have seemingly missed the gist of the authorities' drive to encourage more eco-friendly motoring.

It was wrong to see small cars as basic and poorly manufactured. So is indiscriminately accepting small cars as eco-friendly.

Surely it is remarkable that the unfair bans on small cars, regardless of their performance and quality, are being lifted. But that does not mean emission requirements will be relaxed.

As competition intensifies in the domestic automobile market, manufacturers of small cars are trying to seize market shares by offering vehicles at low prices. But they should not be allowed to obtain a competitive edge at the cost of fuel economy or emission control.

Encouraging the use of small cars is only a means of helping to raise energy efficiency and improve the environment. Do not put the cart before the horse.