On Friday, the NBS released data about industrial companies' profits in the first eight months, showing that they increased by 12.8 percent year-on-year, up 1.7 percentage points from the Jan-July figure.

In August, industrial profits grew 24.2 percent from a year earlier, compared to 11.6 percent in July.

Zhu Haibin, chief economist in China from JP Morgan, said that the stronger-than-expected economic activity data in July and August, plus the solid reading in the manufacturing PMI in September, point to upside potential for the GDP forecast in the third quarter, which may accelerate to 7.6 percent.

China's GDP growth slowed to 7.5 percent in the second quarter from 7.7 percent in the first.

"Manufacturing investment, which has decelerated for the past two years, started to recover in August," said Zhu.

Together with the increasing external demand that has benefited from the improvement in growth outlook in advanced economies, especially in the Euro area, China is likely to maintain the recovery in growth momentum during the short term, he said.

"Nonetheless, we remain cautious on the sustainability of the ongoing recovery. We expect the recovery to last until the end of the year and to slow again in 2014."

The government has accelerated investment in railways and public housing construction, and introduced measures to help small-scale businesses.

Premier Li Keqiang pledged on Monday to "deepen reform across the board for long-term, sustainable and sound economic growth and social progress," especially in fiscal, taxation, banking and investment areas.

On Monday, a separate manufacturing PMI report from HSBC Holdings also posted a slight rise of the figure in September at 50.2, up from 50.1 in August, signaling that operating conditions improved fractionally since the previous month.