The coalition government will hand down the first surplus budget in more than a decade, underpinned by strong iron ore prices and under-spending on disability services.

It will include billions of dollars for road projects and freight networks across regional Australia, along with a raft of other sweeteners such as cash payments for power bills.

But with less than six weeks left until a federal election, keen observers are waiting to see how the government will spend $9 billion in “decisions made but not yet announced” from its most recent economic update.

Cormann has all-but-confirmed there will be extra personal tax relief in the budget, ensuring total taxes don’t rise above 23.9 per cent of the national economy.

“We’ve made the decisions in past budgets and budget updates in order to fulfil that commitment,” he told ABC radio today.

“What Australians will see is that we will continue to fulfil that commitment that we’ve made.”

Treasurer Josh Frydenberg will hand down his first federal budget on Tuesday night.

But Labor is promising to overwrite it immediately if it wins the May election, saying a Shorten government will deliver its own budget before September.

The coalition is planning to spend big money on roads, particularly in Victoria and South Australia.

The budget will also include an extra $1 billion for at least seven freight corrid­ors across Queensland, Victoria, NSW and Tasmania.

The extra money will be directed at roads that feed into major arterial and interstate highways.

Frydenberg on Sunday announced $285 million to help almost four million Australian pensioners and veterans – but not people on the dole – cover their energy bills.

The treasurer also pushed back against criticism that the government’s projected surplus was being built on huge underspending in the National Disability Insurance Scheme.

He argued that wages, which have stagnated in recent years, are picking up compared to the same time last year.

But shadow treasurer Chris Bowen said the coalition had over-estimated the outlook for wages growth in every single budget it had handed down.

Prime Minister Scott Morrison is expected to call an election for May 11 or 18, within days.

-AAP

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