The Agri-Food and Veterinary Authority (AVA) said the tests would begin in the coming months, once scientists had finished examining 1,200 samples of China-made food and drink meant for humans.

'Now that we know there is a problem with milk and milk products, it is wise to continue scanning the horizon,' said an AVA spokesman.

He added that all pet food in Singapore was 'imported from AVA-approved establishments'.

Veterinarians who spoke to The Straits Times said they had not seen any animals with diseases linked to melamine.

Over the last two weeks, 10 products - from crackers to yoghurt bars - aimed at humans had tested positive for the chemical, which was added to Chinese milk to help it pass quality tests.

The presence of melamine in human food came roughly 1 1/2 years after it was discovered in China-made pet food sold in the United States.

Veterinary organisations reported over 100 animal deaths in a scandal that sparked a recall of more than 100 pet food brands in the US.

Since the most recent scandal broke three weeks ago, China authorities had said they would step up checks on livestock feed.

Professor Ong Choon Nam, a toxicologist from the National University of Singapore's Yong Loo Lin School of Medicine, said melamine, if eaten by pets, could, in some cases, form potentially lethal kidney stones, but it could normally be excreted without a problem.

One local laboratory that tests for melamine on behalf of private food and feed companies has found 10 per cent of animal feed samples tainted with melamine.

The samples came from overseas suppliers and were potential product ingredients. They did not necessarily get put on shelves or make it into feed products.

Pacific Lab Services, owned by agricultural product and livestock company Zagro, said the contaminated samples were from overseas sources.

It would not specify if the offending items came from China, citing confidentiality clauses with its clients.

Though Pacific Lab, as a a private entity, does not report cases to the authorities, it advises its clients to reject the batch if it fails safety tests.

Demand for its melamine tests shot up last month following the China reports, peaking at 180 samples this year.

About 70 per cent of the samples were for human food, and the rest for livestock. Only one sample was found contaminated last month, a food product meant for human consumption.