A Labor-led coronavirus parliamentary committee will seek to compel Treasurer Josh Frydenberg to explain how the Federal Government overestimated the JobKeeper wage subsidy program by $60 billion.
Opposition Senate Leader Penny Wong said a COVID-19 committee examining Government measures in response to the coronavirus wanted to quiz the Treasurer about the mistake revealed on Friday.
"Josh Frydenberg hasn't fronted up and taken responsibility," she told Insiders.
"He should do that and we will give him the opportunity.
"The chair of the Senate Committee into the COVID-19 response of the Government, Senator [Kate] Gallagher, will call Josh Frydenberg to give evidence at that committee and what I would say to Josh: 'This is your opportunity to front up and explain $60 billion blunder to the Parliament and to the Australian people'."
© ABC News: Nick HaggartyThe Government initially expected JobKeeper would cost $130 billion, $60 billion more than needed. (ABC News: Nick Haggarty)
The JobKeeper program was initially costed at $130 billion, making it the single biggest piece of Government spending in Australian history.
The Government expected it would cover 6 million workers, paying them $1,500 a fortnight.
On Friday, the Treasury Department and Australian Tax Office revised that to 3 million workers, blaming businesses for making "significant errors" in their applications.
The estimated cost of the program has been nearly halved from $130 billion to about $70 billion.
The mistake occurred on 1,000 businesses' applications, representing just over 0.1 per cent of the 910,000 businesses that have registered for JobKeeper.
On Friday, Mr Frydenberg said the error was "good news" and had been picked up before it had any consequences for JobKeeper payments the Government had already paid.
"It is welcome news that the impact on the public purse from the program will not be as great as initially estimated," he said.
Senator Wong said the program being $60 billion cheaper meant the Government should adopt Labor's calls to expand the program to include more casuals.
Casual workers are only eligible for the program if they have spent more than a year with one employer.
But Mr Frydenberg dismissed those calls and insisted the Government would not reallocate the $60 billion.
Instead, he said it meant future generations would not have as much debt to pay back.