Prices fell again on the Global Dairy Trade auction on Tuesday night.
The auction concluded with the GDT price index down 0.7 per cent.
The average price dipped below the $US3000 a tonne mark for the first time this year to close at $US2980/tonne.
The fall was led by the key whole milk powder index, which was down 2.2 per cent to $US2821/tonne.
The butter index also fell sharply, down 2.8 per cent.
But some commodities bucked the trend with cheddar up 4.2 per cent and skim milk powder up 2.2 per cent.
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