BEIJING -- China's top economic planner has demanded tighter scrutiny over public-private partnership (PPP) projects as the government seeks to boost infrastructure funding while containing fiscal risks.

All PPPs are required to go through a thorough feasibility study, including the project cycle and cost, operation efficiency as well as risk management, according to a notice from the National Development and Reform Commission (NDRC).

PPP projects that do not follow standard procedures are not allowed, the planner stressed.

Public bidding should be the main means of soliciting private capital, the notice said, adding a level playing field should be ensured for fair competition.

The NDRC also pledged severe punishments on malpractice during the implementation of PPPs.

PPPs are a collaborative investment model between government and private companies.

Chinese authorities have explored funding infrastructure and public works through PPP models since late 2013, reducing local government debts and opening new opportunities for private capital.

A total of 8,654 PPP projects had been registered in a national data bank by the end of 2018, according to data from the Ministry of Finance.