Warning issued over global economy risks (2)

Zhang said most developed economies will face the challenge of "Japanization", high debt and an aging population.

This could result in growing protectionism, he said, and China may be its major victim.

The report also focused on the shrinking US trade deficit. It has fallen from 6 percent of the GDP in 2006 to an estimated 3.1 percent in 2012.

The trade surplus in China may be lowered to 2.3 percent of its GDP this year from 10.1 percent in 2007. Sun Jie, a senior research fellow with the academy, said the trend for both countries will continue over the next year.

Fan Jianping, deputy director of economic forecast at the State Information Center, another government think tank, wrote in a report that China faces three possible scenarios.

In the basic scenario, Fan said, growth will be 8 percent in 2013 if issues like the eurozone crisis and fiscal cliff are properly handled.

Growth, in the second scenario, may even reach 9 percent if the global trade environment improves.

The worst scenario would involve the US falling off the cliff and the eurozone crisis remaining unsolved.