Prime Minister Scott Morrison has denied the federal budget is aimed at buying votes, saying anyone who thinks it is solely a bid for re-election needs to “read more than the first page”.

In his fourth budget on Tuesday night, Treasurer Josh Frydenberg promised lower fuel prices and cash to ease cost-of-living pressures.

Revealing a halving of the fuel excise and a one-off $420 tax offset for 10 million low and middle-income earners, Mr Frydenberg boasted Australia’s economic recovery from COVID-19 was “leading the world”.

Mr Morrison said his government’s planned investment in infrastructure showed it had a long-term plan.

“People need to read more than the first page [of the budget] because there’s $21 billion of investment in our regions,” he told the Seven Network on Wednesday.

“More than 80 per cent of our goods exports come from our regional areas, and in this budget is the single largest transformational investment in our regions to grow Australia’s wealth.”

He described handouts for millions of Australians as a “shield” against cost of living pressures.

“The budget has turned around by some $100 billion, by getting people off welfare and into work,” Mr Morrison told the ABC.

“The budget has strengthened, the economy has strengthened. So we could give people a shield – whether they be pensioners or hard-working families, those paying for prescription medicines, filling up the car at the bowser, we gave them a shield against the cost of living increases caused by what is occurring in Ukraine.

“But it makes it real and the package of support is real and it’s needed now and it’s responsible and it’s targeted.”

Tweet from @leighsales

In a surprise move on Wednesday, Mr Morrison pulled out of a key TV interview as the Coalition continued a post-budget media blitz. He had been due to appear on the ABC’s 7.30, but it was abruptly cancelled.

Host Leigh Sales tweeted the decision, saying Mr Morrison would join her instead next week.

News Ltd reports the interview clashed with Mr Morrison’s plans to attend the memorial service for Shane Warne at the MCG on Wednesday night.

A spokesperson for Mr Morrison’s office told News that his plans had to change to allow him to get to Melbourne in time for the state service. Opposition Leader Anthony Albanese will travel with the PM.

The ABC interview would have also followed an incendiary speech by ousted Liberal senator Concetta Fierravanti-Wells, who labelled Mr Morrison a bully and “unfit to be PM” in an address to the Senate on Tuesday.

The federal budget unveiled by Mr Frydenberg on Tuesday also includes short-term measures such as a one-off $250 payment to be delivered within weeks to six million pensioners, carers, veterans, job-seekers, eligible self-funded retirees and concession card-holders.

Mr Frydenberg said the handouts were about helping change people’s lives, immediately. But he admitted the low and middle-income tax offsets wouldn’t last forever.

“We aren’t continuing the low and middle-income tax offset indefinitely … It was always a temporary measure and we would bring it to an end but actually people are paying lower taxes because we have engaged in structural reform.”

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Labor spokesman Jim Chalmers said there were secret cuts to the tune of $3 billion.

“[The budget] has two years of spending that they haven’t announced yet – before the election – and then it’s got three years of cuts after the election, secret cuts,” he told ABC Radio National.

“Josh Frydenberg needs to come clean: What are his $3 billion in secret cuts that he doesn’t want to fess up to until after the election?”

Mr Albanese said the federal government “might as well staple cash to how-to-vote [cards]” for people as they enter polling booths this May.

“It all disappears once the election is over and done with, that’s the problem with this budget,” he told the Seven Network.

“It’s a cynical ploy to get the government through an election, not a plan for a better future for Australia.”

A further measure in the budget will mean people will need fewer scripts before they are eligible for free or further discounted medicines.

Small businesses will get a tax deduction for training employees and investing in new technologies such as web design and cyber security.

New apprentices will be encouraged with $5000 payments and up to $15,000 in wage subsidies for employers.

With Russia deploying cyber warfare alongside its invasion of Ukraine, the government revealed a $9.9 billion spend on the Australian Signals Directorate to put more computer professionals on the front line.

The funding comes alongside a $38 billion boost in the defence workforce.

Mr Frydenberg said the government was spending responsibly, with the budget deficit of $78 billion in 2022/23 narrowing to $43.1 billion in 2025/26.

Easing the pressure is the forecast jobless rate of 3.75 per cent, which is putting a lid on welfare spending.

Mr Albanese will deliver his budget reply on Thursday.

-with AAP