The bureau said the net export figure would contribute 0.2 of a percentage point to Wednesday's GDP figures.

While rural exports took a big hit, down $364 million or 3 per cent in the quarter because of the drought, there was also a drop in coal exports, down 10 per cent in value terms and 4 per cent in volumes.

However, iron ore and minerals were up 4 per cent, or $1.4 billion, driven by both price and volume.

Import volumes fell 0.2 per cent in the quarter and are now down 1.5 per cent in the year.

Westpac's Andrew Hanlan noted this was a worry given the weak domestic demand and lower Australian dollar.

On the income side of the current account ledger, record low interest rates resulted in a significant decline in interest payments flowing out of the country. This helped Australia narrow its net income deficit to $13 billion.

Overall economists expect the current account surplus to continue next quarter.

"We expect an ongoing current account surplus position in 2020," Citi's Josh Williamson said.

Separately on Tuesday, government finance figures were released showing that general government final consumption expenditure increased by $817 million or 0.9 per cent, and this is expected to contribute 0.2 percentage points to growth in the September quarter GDP figures.

NAB upgraded its GDP forecast to 0.5 per cent for the quarter and 1.6 per cent for the year, from 0.3 per cent and 1.5 per cent respectively, due to the increase in expected government expenditure.

"The revision reflects stronger public demand than NAB had forecast – adding 0.3 percentage points to GDP against our expectation of a 0.1 percentage point contribution," NAB's Kaixin Owyong said.