Jim Chalmers is pledging to save more than he spends in the Budget due in just over a week, as the Cabinet prepares to make the final decisions on its measures.

The Treasurer says his “most responsible yet” Budget papers will show a net saving for the second time in a row and larger-than-usual cuts.

He’s also looking to bank all upward revisions to revenue – despite last week playing down suggestions from economists that the government was in line to reap as much as $30 billion in windfall tax take because of the Iran war and growing inflation.

“There will be more savings and more spending restraint helping to pay down more of the trillion dollars of debt that the Liberals left behind,” Dr Chalmers said.

Already, the Government has outlined $38 billion in savings from the NDIS and lowering the private health insurance rebate paid to over-65s.

But it has also identified more than $65 billion in new spending.

This includes $25 billion for hospitals, $14 billion on Defence, inflation-driven increases in welfare payments and the age pension, the cut to the fuel excise, and natural disaster support.

Assistant Treasurer Daniel Mulino said any decision on extending the $2.5 billion fuel excise cut beyond the end of June would likely be made after the Budget.

The Government will also use the Budget to extend tax breaks for commercial television and radio broadcasters for another two years, to mid-2028, saving the media organisations $111.3 million.

It revealed over the weekend $1.8 billion will be set aside to continue funding urgent care clinics.

But Dr Chalmers and Finance Minister Katy Gallagher intend to keep average real spending growth low and payments below 27 per cent of GDP.

Last year’s budget showed spending hit 27 per cent of GDP and was already forecast to drop over the coming years. The Government has come under sustained presser to cut spending as part of efforts to contain growing inflation.

The May 12 Budget is widely expected to include cuts to capital gains and negative gearing tax concessions for property investors. It may also increase taxes on trusts.

None of these were mentioned ahead of the election a year ago.

But Dr Mulino argued that people expected governments to be “developing a broader agenda” to tackle long-term challenges.

“The election promises that we took to the last election were the foundation ... but look, we will do other things this term, and that’s part of what people expect governments to do,” he said.

The Opposition has said it is broadly against tax increases, but won’t commit to voting against the housing tax changes or repealing them before it sees details.

However, Nationals leader Matt Canavan on Sunday compared it to the Hunger Games, “where they’re looking to take from some people and give to the others”.

Prime Minister Anthony Albanese wouldn’t give any assurances to existing investors that tax breaks would be maintained for any properties they now hold.

He said young people “feel like they’re not getting a fair crack at the moment”.

“I want Australia to be a land of opportunity for the future ... any changes that we put in the Budget, or indeed while we’re in government, will be very much focused on those principles,” he said.

“I think it will be a Budget of which I’m very proud and the Government can be proud as well.”

Shadow treasurer Tim Wilson will rubbish this argument in a speech to business leaders on Monday, saying the Prime Minister’s claim to focus on intergenerational equity was instead “fuelling fights over Sunday roasts”.

“Labor is building a class of Australians dependent on them being in office. This government is not about a better Australia, it is about securing power,” he will tell the Australian Chamber of Commerce and Industry, according to a draft of his speech.