CHINA has stopped all milk powder imports from New Zealand after the type of bacteria that can cause botulism was found in products from the country's biggest milk exporter, Fonterra.

China is the largest importer of dairy products from New Zealand, with 80 per cent of China's imported milk powder coming from the country, Xinhua reported.

Fonterra, the world's largest dairy exporter, said 40 tonnes of its whey protein had been contaminated with clostridium botulinum, which can cause botulism, damage muscles and even cause respiratory failure.

New Zealand Trade Minister Tim Groser told television audiences that Chinese authorities had imposed the ban on all milk powder products from the country, including those shipped through Australia.

"It's better to do blanket protection for your people and then wind it back when we are in a position to give them the confidence and advice that they need before doing that," Mr Groser said.

They are Shanghai Yanjiu; Dumex Baby Food, a Danone brand; and Wahaha Health Food and Wahaha Import & Export, both of which are under the Chinese food and beverage giant Hangzhou Wahaha.

Representatives from Coca Cola (China), Dumex and Hangzhou Wahaha Health Food, which had purchased some of the imported whey protein from Shanghai Yanjiu, were summoned to the State Food and Drug Administration.

The regulator urged them to stop sales of such products and to recall all goods produced using potentially tainted materials.

Dumex, which imported 209 tonnes of whey protein from Fonterra, said 12 batches of baby formula were produced from the problematic raw material, amounting to 664 tonnes.

Coca-Cola said that nearly five tonnes of imported whey protein had been safety quarantined and that 25 kilogrammes had been used to produce bottled Minute Maid fruit milk.