BEIJING, Oct. 14 (Xinhua) -- Chinese authority has intensified efforts to encourage private sectors to participate in infrastructure investment in seek of healthy economic growth.

By the end of September, at local level, some 1,222 infrastructure projects worth at least 2.5 trillion yuan (362 billion U.S. dollars) have been promoted among private companies, according to the National Development and Reform Commission (NDRC), China's economic planning agency.

Private companies have shown cooperation intention in 150 projects worth at least 250 billion yuan, the NDRC said in a statement on its website.

At the end of September, private companies inked eight airports construction agreements with investment totaling nearly 50 billion yuan.

Infrastructure projects comprise of energy, transportation, highway, garbage disposal facilities and reservoirs.

The country's private investment, which accounts for more than 60 percent of the total fixed-asset investment, rose 8.8 percent year on year in the first seven months of the year, and 8.4 percent in the first half of the year.

At the end of 2017, private businesses accounted for more than 60 percent of China's GDP and provided more than 80 percent of urban jobs.