WELLINGTON - New Zealand agricultural authorities on Friday moved to reassure dairy food consumers in China that its products are safe.

The two New Zealand makers of agricultural chemicals announced Thursday they had suspended sales of a product that stopped nitrate leaching amid fears the residues could harm the country's valuable international dairy trade.

Ravensdown and Ballance Agri-Nutrients voluntarily suspended sales and use of Dicyandiamide (DCD) treatment for farm land until further notice.

A Ministry for Primary Industries (MPI) spokesperson told Xinhua on Friday that DCD residues had not affected dairy products exported to China.

"There is no food safety issue and this is a voluntary suspension of a product applied to pasture. It is a proactive step to ensure New Zealand's export markets, including China, remain confident in the high quality of New Zealand milk products," she said in an e-mail to Xinhua.

"The New Zealand government's diplomatic post in China is briefed about DCD and will be talking to their counterparts in China if required."

The ministry believed that only "a very small amount of product " might contain residues.

"This is because only 5 percent of New Zealand dairy farmers have been using DCD and DCD affects a limited number of dairy products for a short window of time that follows its use two to three times a year," she said.

Exports of dairy products make up a quarter of New Zealand's total exported goods by value, and last year their total export value was NZ$14.5 billion($12.13 billion).

Milk powder, butter and cheese exports were up by 25 percent, or NZ$184 million, month on month in November last year, according to Statistics New Zealand.