The Australian sharemarket will open weaker on Monday as investors brace for the federal budget and more uncertainty about US President Donald Trump’s tariff agenda.

The S&P/ASX 200 futures indicate the index will decline 41 points, or 0.5 per cent, after the sharemarket posted its strongest weekly gain this past week. The benchmark is still down almost 3 per cent this year, having briefly entered a correction, defined by a 10 per cent drop from peak to trough.