Sri Lanka has temporarily suspended releasing imports of milk powder from New Zealand after reports of contamination, officials said in Colombo on Tuesday.

Health Ministry Secretary Palitha Mahipala told media that he had taken the decision to suspend distribution of New Zealand imported milk powder after a warning was released over the weekend.

Stocks of milk powder that have already reached the Colombo port will not be cleared until tests on samples come back negative.

New Zealand warned international health authorities on Saturday of exported dairy products, including infant formula, containing a bacteria that could lead to botulism, a potentially fatal illness.

The government said the contaminated whey protein concentrate, or products using this ingredient, had been exported to Australia, China, Malaysia, Saudi Arabia, Thailand and Vietnam.

Dairy giant Fonterra, which manufactured the product more than a year ago, said eight customers had been advised and is investigating whether any of the affected products was in their supply chains.

China and Russia stopped imports following the announcement.

The botulism warning has added to the Sri Lankan government's earlier concern that the milk powder imported to the country contains traces of dicyandiamide (DCD), an agrochemical.