US consumer prices rose by 4.2 per cent in April compared to a year ago, the biggest jump in inflation since 2008.

The higher than forecast inflation rate was driven by supply bottlenecks in raw materials such as computer chips and timber as well greater demand for second-hand cars and trucks following the lockdown.

Economists had forecast a jump in prices of around 0.2 per cent but in the event the monthly consumer price index rose by a hefty 0.8 per cent, the biggest monthly increase since 2009. It was also a significant rise on the 2.6 per cent annual increase seen in March.