Australia's unemployment rate surged to 6.4 per cent in January, making its surprise fall to 6.1 per cent in December short-lived.

The Australian Bureau of Statistics said on Thursday that the number of people employed fell by 12,200 to 11.668 million in January, against market expectations of a fall of 5,000.

This took the official unemployment rate to 6.4 per cent from 6.1 per cent in December, while the participation rate remained steady at 64.8 per cent of the population.

The figures were well below expectations, and the Australian dollar plunged more than half a US cent, to US76.63 cents.