Weak external demand and slack domestic investment could drive China's economic growth down to 7 percent next year from about 7.3 percent this year, the country's leading think tank warned on Monday.

The Chinese Academy of Social Sciences said that 7 percent would still represent "fast and stable" growth sufficient to accelerate structural reform and maintain a healthy labor market.

Consumer inflation may drop to 1.8 percent next year from about 2 percent in 2014, exacerbating deflationary pressure, it said.