No melamine was found in 224 samples of dairy products imported from 18 countries and regions, China's quality watchdog said yesterday.

Meanwhile, it issued an urgent circular on Wednesday, ordering inspection and quarantine departments nationwide to increase melamine tests on imported and exported feed, with a view to "ensuring safety of feed and feed additives".

The State Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) required local departments to improve supervision over feed import and export companies, increase sample proportion for melamine tests, strictly look into the responsibility of relevant companies' product safety officials and work with local customs to trace fake quarantine certificates and illegal activities such as escaping from inspections.

It would soon organize spot tests on feed exporters in key regions and list those with bad records. Local departments would hand law-violating cases to the police, said the circular.