GUANGZHOU -- The economic slowdown in Guangdong during the first half of the year was more severe than expected, according to the governor of the southern province, China's economic powerhouse.

Growth in gross domestic product, investment, expenditure, foreign trade and financial revenue were all lower than the targets for the full year and the national average level, Zhu Xiaodan told a seminar on the provincial economic situation on Wednesday.

Guangdong's GDP in the first half year was expected to reach 2.67 trillion yuan ($423 billion), or up 7.4 percent from the same period of last year, according to Zhu.

Fixed-asset investment rose 10.1 percent year-on-year to 769.75 billion yuan, while export rose 6.9 percent from a year ago to reach $218.52 billion, he said.

Zhu said a long-term structural problem and economic fluctuations were to blame for the slowdown.

Guangdong is considered a weather vane for China's economy as it generates more than a 10th of the country's GDP.

The National Bureau of Statistics is scheduled to release key monthly and quarterly economic indicators on Friday.

Analysts have predicted that China's economic growth will fall under 8 percent in the second quarter.