China's banking regulator has asked trust companies to strengthen risk management, underlining the responsibility of shareholders and forbidding shadow banking business.

Trust companies are required to implement comprehensive risk control in product design, risk supervision and information disclosure, according to a guideline released by the China Banking Regulatory Commission.

The guideline contains specific stipulations for the companies' shareholders, who are obliged to provide liquidity support in the case of liquidity risk.

The guideline also ruled out non-standardized investment business related to shadow banking, such as cash pooling, and asked companies providing similar services to draft and submit plans to regulators to rectify their products by the end of June.

Analysts said trust companies should rectify cash pooling in an orderly manner to prevent liquidity problems, as the business, having accumulated potential risks, makes up a substantial proportion of the companies' business structures.

The CBRC encouraged trust companies to restructure their business and focus on traditional services, including equity investment, mergers and acquisition services and assets management.