China may see its final consumption reach 5 trillion U.S. dollars in value by 2015, surpassing Japan as the world's second largest consumer, a senior government official has projected.

Wang Xuanqing, deputy director of the Department of Commercial Services Administration with the Ministry of Commerce, made the forecast Friday based on an average annual 11.6-percent growth in consumption in China since 2000.

However, Wang said China's domestic consumption was still weaker per capita than that in many developing nations. He made the remarks at a retailers conference held Friday in Chengdu, capital of southwest China's Sichuan Province.

"If consumption remains too weak for too long, economic growth will depend more and more on investment and exports," Wang said.

"But investment and exports are increasingly meeting restrictions from resources, environment, and international market changes," Wang said, adding "an economy with weak consumption is not sustainable."

Data from the country's National Bureau of Statistics showed China's retail sales rose 18.7 percent year on year to 1.25 trillion yuan (183 billion U.S. dollars) in May, with total retail sales up 18.2 percent to 6.03 trillion yuan in the first five months.

As part of the county's stimulus package, the Chinese government has introduced a host of subsidies for home appliances, old-for-new programs, and tax cuts for auto purchases to boost domestic consumption.

Final consumption consists of goods and services used up by individual households or the community to satisfy their individual or collective needs or wants, according to the definition of the Organization for Economic Cooperation and Development.