SHANGHAI, June 26 -- Shanghai's food watchdog will grade the city's big and middle-sized restaurants based on sanitation in coming months and publish the results on its Website, a senior food official said yesterday.

The Shanghai Food and Drug Administration will grade more than 10,000 restaurants according to their sanitation, said Gu Zhenhua, director of the food supervision department under the administration.

The restaurants will be divided into four grades and the food regulator will strengthen the supervision on restaurants with lower grades.

Grade A restaurants will be checked twice a year, grade B will four times, grade C six times and eight times for grade D.

If a restaurant's causes food poisoning in customers or makes them sick, it will be degraded to D. If a restaurant is graded C for two consecutive years, it will also be degraded to D.

The grading system will be expanded to small restaurants in the future, Gu said.

China's Ministry of Health has launched a campaign in Hangzhou, the capital of Zhejiang Province, to label sanitary restaurants with a "smiling face" at the gate and dirty restaurants with a "bitter face."