A major global credit ratings agency has again expressed concerns about Australia's ability to repair the budget in the face of a "splintered Senate".
However, Moody's Investors Service says Australia's triple-A rating remains supported by sustained robust growth, even as the economy adjusts to dampened revenue due to lower commodity prices.
Figures on Wednesday are expected to show annual economic growth remaining above a solid three per cent pace, even though over the June quarter expansion is expected to be much slower than in the first three months of the year.
Moody's says while Australia's government debt burden is moderate compared to similarly rated peers, the Turnbull government will face challenges in narrowing the budget deficit at the pace envisaged in the May budget.
"Moderate nominal GDP (gross domestic product) growth continues to weigh on revenues and a splintered Senate makes passing budget consolidation measures politically challenging," senior vice-president Marie Diron said in a report released on Monday.
In a message aimed at Labor and the cross bench, Treasurer Scott Morrison said the government took to the July 2 election a budget trajectory which had the support of global rating agencies.
"There is a clear plan that has been set out there for getting the budget back to balance," he told reporters in Sydney.
"The Australian people just expect the parliament to get on with it, not to play games, not to engage in these sort of political stunts that we've been seeing."
In a separate report, the Grattan Institute think tank backed the government's proposals to wind back superannuation tax breaks as a "first stride" to making the system fairer.
But it warned if the government couldn't get its reforms through parliament, there was little hope for either budget repair or wider economic reform.
The institute's head, John Daley, went as far as labelling it as an "acid test" for the Australian political system.
But Mr Morrison believes the real test is the acceptance of the measures in a $6 million budget savings bill introduced to parliament last week.
"Those measures do go to the heart of testing the mettle of this parliament about whether they're serious about arresting the debt or not," he said.
New figures ahead of Wednesday's national accounts showed company gross operating profits grew by a sprightly 6.9 per cent to $63.7 billion in the June quarter, while business inventories are expected to add 0.2 percentage points to GDP.
At this stage, economists are forecasting June quarter growth to be 0.4 per cent compared to 1.1 per cent in the previous three months, for an annual growth rate of 3.2 per cent.
However, estimates might change after quarterly international trade and government spending data on Tuesday.
