China plans to limit foreign investors' investment proportion in new projects for key components of new-energy vehicles to under 50 percent, the National Business Daily (NBD) reported.

This is the first time that China's authorities clearly defined the investment proportion of joint ventures producing key components for new-energy cars, NBD said.

According to the guide co-issued by the National Development and Reform Commission and Ministry of Commerce, the key components include a wide range of car parts such as power battery, cathode material, battery management system, motor management system and drive motor.

The new guide will not only set a threshold for transnational corporations to establish new auto parts companies in China but also extend the restrictions to some traditional car parts.