Mounting expectations of further US interest rate cuts helped drive the dollar to a lifetime low against the euro yesterday, which in turn boosted oil and gold prices to new highs, as Ben Bernanke, Federal Reserve chairman, reiterated concerns about economic growth.

In his semi-annual testimony to the House financial services committee in Washington, Mr Bernanke repeated that the US central bank would act in a "timely manner'' as the economic situation had become "distinctly less favourable". He also said that inflation was picking up and that the public's expectations for price increases might also be rising.