The Australian dollar is worth more than the US dollar for the first time since it became a freely traded currency, following comments by the Federal Reserve chairman, Ben Bernanke, that the US was likely to pump more money into the struggling American economy.

The comments put further pressure on the US dollar, which has been on the slide in recent days on growing talk that the US was preparing to initiate a second round of quantitative easing to avoid the risk of a double-dip recession.

Speaking at a conference organised by the Boston Federal Reserve, Bernanke said that high unemployment and low inflation meant further action would be needed to ease US monetary policy. He said: "There would appear – all else being equal – to be a case for further action." But policymakers are still discussing how aggressive they needed to be.

Bernanke's comments came just ahead of news that the US inflation rate rose by 0.1% in September compared with forecasts of 0.2%, helping push the US currency lower against other major currencies. The Australian dollar rose to $1.004, finally rising above parity thanks to the country's higher interest rates and resources-driven growth. The euro was trading at $1.40968, up 0.2% on the day, while the dollar fell to 81.06 yen, down 0.5%. Sterling rose to an eight-month high of $1.61.

Meanwhile, gold moved to a high of $1,385 an ounce as the US currency weakened.