The Australian dollar is back below 77 US cents, under pressure from falling metals prices, amid market caution about higher US interest rates and worries about a possible trade war.

At 0635 AEDT on Wednesday, the local currency was worth 76.84 US cents, down from 77.06 US cents on Tuesday.

Copper prices are at their lowest levels in more than three months, and gold is also lower as the US dollar strengthens ahead of a US Federal Reserve meeting at which the US central bank is expected to raise interest rates for the first time this year.

AAP

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