International milk prices fell while volumes dropped in this month's first auction held by New Zealand's Fonterra Co-operative Group, the world's biggest dairy exporter.

Fonterra's GDT Price Index dipped 0.3 percent, with an average selling price of $2,649 per tonne, in the auction held on Tuesday.

The index rose 1.4 pct at the previous sale, said Fonterra, which is known for brands such as Anchor, Anlene and Fresh n' Fruity.

A total of 45,499 tonnes was sold at the latest auction, falling 10.5 percent from the previous one, the cooperative said on its website (www.globaldairytrade.info).

The auctions are held twice a month, with the next one scheduled for November 18.

The auction results can affect the New Zealand dollar as the dairy sector generates more than 7 percent of the nation's gross domestic product.

The New Zealand milk co-operative, which is owned by about 10,500 farmers, controls nearly a third of the world dairy trade. (Bangalore Commodities desk)