The Australian economy rebounded to expand by an annualised 1.9 per cent in the first quarter but the improvement was weaker than expected and may be short-lived because it was fuelled by a build up in inventories.

Data released Wednesday showed gross domestic product rose 0.7 per cent in the first three months of the year, up from 0.3 per cent in the fourth quarter, a revision from the 0.1 per cent initially announced.