Federal Labor has attacked the Morrison government for spending cuts over the forward estimates claiming there is a big gap in the budget beyond the imminent cost of living relief.
Labor's treasury spokesman, Jim Chalmers, said Treasurer Josh Frydenberg's budget included more than $3 billion in secret spending cuts over the coming years.
Tuesday's budget revealed a $20.9 billion improvement in the bottom line with the 2022-23 underlying cash deficit to sit at $78 billion.
Dr Chalmers said Labor would vote with the government to pass the cost of living package, which includes a six-month 50 per cent reduction in the fuel excise tax in a bid to ease petrol prices at the bowser.
But Dr Chalmers said "decisions taken but no yet announced" in the financial measures showed $3 billion in cuts over the next three financial years.
"The Australian people deserve to know. Is it pensions? Is it Medicare? Is it something else?" he said on ABC RN. "We shouldn't be going to the election with those secret cuts in the budget that will only be unleashed on the Australian people if the Coalition is returned."
Prime Minister Scott Morrison during Question Time hit back at Labor's spending cut accusations claiming the opposition needed a dummies guide to reading the budget.
"The line item name shows the change from last year's mid-year budget update of decisions taken but not yet announced and not the publication list," Mr Morrison said when responding to a question from Dr Chalmers.
"Now what that means is when that number goes in the negative it means that other numbers have gone into the positive. It comes out of that column and it goes in in another column, genius."
Over in the Senate, ACT Labor senator Katy Gallagher also had a crack at the $3 billion spending cut question, with Finance Minister Simon Birmingham saying it was a foolish comment.
In a supplementary question, Senator Gallagher said the budget was a cash splash ahead of the May election.
Greens leader Adam Bandt in his budget reply outlined the government supported tax cuts for the wealthy and did not address Australia's housing affordability crisis.
The federal government effectively doubled the number of places on New Home Guarantee scheme. However no policies were announced to address housing supply issues.
Mr Bandt said the budget was further dismantling Australia's progressive tax system.
"The tax measures in this budget, which Labor backs, will see someone on the minimum wage pay the same tax rate as a CEO," he said. "There's $13 billion of public money to push up housing prices, but no new money to build affordable homes."
Mr Frydenberg's budget outlined a $420 one-off tax offset for low and middle income earners, while pensioners will receive a $250 cash payment.
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