A bill is being drafted to tighten control on food with a higher safety risk or of wide public concern, focusing on strengthening food tracing system, said a Hong Kong health official Saturday .

Speaking on a radio talk show, Permanent Secretary for Health, Welfare and Food Bureau of Hong Kong Carrie Yau said a reliable system in tracing the source of problematic food is crucial to protecting public health.

The bill will include an effective importer and supplier registration system, and also state clearly the responsibilities of importers and under what circumstances the food in question must be recalled, she said, adding that experience in other countries is an important reference in drafting the bill.

Yau said, the Hong Kong government will explore with authorities of the Chinese mainland on how to improve the food regulatory mechanism, such as widening the scope of imported food that needs to be accompanied with health certificates and putting more categories of food under regulation and control.

She said about 90 percent of Hong Kong's food is from the Chinese mainland, and some have connection with food safety issues, but it does not mean the food from the mainland is unsafe.