Treasurer Scott Morrison says Labor’s budget strategy is a “complete lottery”, changing from one day to the next.

Labor released its 10-year economic plan last week, which involves greater deficits over the four-year budget estimates but still brings a surplus in mid-2021 – the same as the coalition government – a strategy economists fear threatens Australia’s triple-A credit rating.

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It has also backflipped on some measures that it has previously opposed – the so-called “Zombie cuts” – budget savings not yet passed by the parliament and never likely to pass.

Asked on ABC television whether he expects further reversals on policies, Mr Morrison said: “Who knows?”

Brendan O’Connor says Labor is being ‘upfront’ with voters. AAP

“I don’t know what they are doing from one day to the next because it seems to change every single day,” Mr Morrison said.

He said Labor is opposed to business tax cuts now, but two years ago they were for them.

But opposition frontbencher Brendan O’Connor said Labor is being upfront with voters.

“I do believe the Australian public are sick to death of governments saying one thing and doing another,” Mr O’Connor told Sky News on Sunday.

“We are presenting the details in order for people to make an informed decision.”

However, Mr Morrison said there was nothing in last week’s Labor press conferences that gave any year-by-year projections on revenue or other savings measures.

Opposition Leader Bill Shorten will announce an extra $2 billion of funding for public hospitals on Sunday if it wins the July 2 election, returning to the former Labor government’s 2011 funding agreement with the states and territories.

Mr Morrison said Labor is making promises with money that isn’t there.

“I think Australians … might like to hear what Bill Shorten’s saying when it comes to some of these things but they also know you can’t pay for things with money that isn’t there,” he said.