At 0700 AEST on Tuesday, the local currency was trading at 77.24 US cents, down from 78.13 cents on Monday.
The Australian dollar began tracking lower on Monday night before plunging around midnight, around the time RBA governor Glenn Stevens began his speech in New York, flagging the possibility of further rate cuts.
“The board has, moreover, clearly signalled a willingness to lower it even further, should that be helpful in securing sustainable economic growth,” he said.
Westpac senior market strategist in Wellington, Imre Speizer, said the Australian dollar also took a hit from the stronger greenback.
“The US dollar is moderately firmer amid further news of a Greek cash crunch and intensifying speculation it may eventually exit the Eurozone,” Speizer said.
“The RBA’s Stevens helped the Australian dollar underperform.”