The decision was made following discussions by a team of feed consultants, including representatives from the husbandry and aquaculture departments under MARD and the Ministry of Health. The permitted level was set with reference to melamine standards in other countries such as the US, Canada and the European Union.

In principle, Viet Nam did not allow the use of any food products contaminated with melamine, including cattle feed, said head of the husbandry department Hoang Kim Giao.

"But the allowed level of 2.5mg of melamine in 1kg of animal feed is equal to zero and MARD made the decision after consulting regulations on melamine standards from many countries around the world," he said.

Under the decision, all feed with higher levels of melamine will be banned from import, production, trade and use in husbandry and aquaculture.

Earlier, MARD banned the import and trade of all materials contaminated with melamine to produce animal feed.

Businesses would have to test melamine themselves on samples of high-risk materials such as fish powder, milk and milk products. Any products testing positive for melamine must be reported to the department as soon as possible.

Melamine is added to foods to artificially boost protein levels but is harmful to humans and can cause kidney damage.