A botulism scare has prompted China and Russia to stop importing certain dairy products from New Zealand.

On Saturday, the New Zealand dairy giant Fonterra announced that up to a thousand tons of infant formula, sports drinks and other products sold in seven countries could be tainted after tests found bacteria in its whey protein that could cause botulism.

The Acting Director-General of New Zealand's Ministry for Primary Industries, Scott Gallacher, said on Monday that China had halted imports of all Fonterra milk powder and whey products. He also said Russia has imposed a wider ban on all New Zealand dairy products.

Doubts reportedly first surfaced over the product following a series of tests in May 2012. Over the weekend, companies and health authorities in China, New Zealand and Malaysia announced specific product recalls of infant formula.