Rio Tinto has warned customers are turning cautious but says it's still able to sell all the commodities it can produce.
Earlier this month, BHP Billiton said some buyers were facing tighter access to credit.
Rio TInto chief executive Tom Albanese says continuing stresses in the euro zone and a weaker forecast for the US economy are affecting customer sentiment, which had become more downbeat in recent months.
The giant mining group intends to sell its New Zealand and Australian aluminium assets, including the Tiwai Point smelter at Bluff.
