Sept. 20 (Bloomberg) -- Fonterra Cooperative Group Ltd. told New Zealand's embassy in Beijing on Aug. 14 that its Chinese partner Sanlu Group Corp. may be using milk contaminated with the industrial chemical melamine, according to the New Zealand Ministry of Foreign Affairs and Trade.

New Zealand authorities first notified China's central government that the goods may be tainted on Sept. 9, more than three weeks later, the ministry said in an e-mailed statement today. China announced a probe on Sept. 10, and the next day the Ministry of Health said milk powder made by Sanlu may cause kidney stones in infants.

``There was insufficient information'' for the New Zealand embassy to notify the foreign affairs ministry in Wellington until Aug. 31, the statement said.

Fonterra Chief Executive Officer Andrew Ferrier last week said local and regional officials in China took too long to issue a public warning that milk being made and sold in China contained the chemical, which is used in making plastics and tanning leather.

To contact the reporter on this story: Lee Spears in Beijing at lspears2@bloomberg.net

Last Updated: September 20, 2008 04:32 EDT