China Set to Act on Fuel Economy; Tougher Standards Than in U.S. By KEITH BRADSHER:

The new standards are intended both to save energy and to force automakers to introduce the latest hybrid engines and other technology in China, in hopes of easing the nation's swiftly rising dependence on oil imports from volatile countries in the Middle East.

They are the latest and most ambitious in a series of steps to regulate China's rapidly growing auto industry, after moves earlier this year to require that air bags be provided for both front-seat occupants in most new vehicles and that new family vehicles sold in major cities meet air pollution standards nearly as strict as those in Western Europe and the United States.

And here's a little gem:

The Chinese rules do not cover pickups or commercial trucks. According to General Motors market research, there is little demand for pickup trucks in China except from businesses, because the affluent urban consumer who can afford a new vehicle regards pickup trucks as unsophisticated and too reminiscent of the horse-drawn carts still used in some rural areas.

Still,

The new standards would require all small cars sold in China to achieve slightly better gas mileage than the average new small car sold in the United States now gets, according to calculations by An Feng, a transportation consultant who advised the government on the rules. But officials in Beijing would require much better minimum gas mileage for minivans and, especially, S.U.V.'s than the average vehicle of either type now gets in the United States.

...

The Chinese standards would require the greatest increases for full-size S.U.V.'s like the Ford Expedition, which would have to go as much as 29 percent farther on a gallon of fuel in 2008 than they do now in the United States, Mr. An calculated. Sport utility sales in China have more than doubled so far this year, but are still a much smaller part of the overall market than they are in the United States.

And anyway, there's some doubt about the efficacy of imposing minimum fuel economy standards instead of raising taxes:

In the United States, G.M. has argued that tighter fuel economy rules are unnecessary because technological improvements will someday improve efficiency anyway. G.M. and other automakers have also contended in the United States that higher gasoline taxes would represent a better policy than higher gas mileage standards, because it would give drivers an economic incentive to choose more efficient vehicles and to drive fewer miles.

China is still considering its policy on fuel taxes, but has not acted so far, because higher fuel taxes would impose higher costs on many sections of society, Mr. Zhang said.

It's not just GM. As Megan McArdle pointed out with regard to the US Corporate Average Fuel Economy standards, increasing fuel efficiency lowers the costs to users, so they use more. If the goal is lower fuel consumption, raising taxes is the answer, but the Americans don't want to do that any more than the Chinese.
(I can only access her through proxies like this). See also this .pdf article.