The Australian dollar fell to its lowest level in a week after the head of the central bank hinted at a possible rate cut or bond purchase.
In general, the atmosphere of risk aversion kept the US dollar supported and the rest of the major currencies on the defensive, unlike the British pound, which held on to the gains it made the previous day thanks to indications of progress in the Brexit talks.
The Reserve Board Governor Philip Low said in a speech in Sydney that the bank was assessing whether buying longer-term bonds would help the economy as it was considering lowering interest rates.
The Australian dollar fell nearly 1%, its lowest level in a week at 0.7096 against the US dollar. It also fell 0.5% against the New Zealand dollar and 0.8% against the Japanese yen.
The US dollar index traded at 93.47, near its highest level in a week, despite most of the major currencies stabilizing in early European trade.
The euro last traded at $ 1.1740, and the US currency was 105.95 Japanese yen.
The sterling settled at $ 1.30 and 90.23 pence against the euro.