Opposition Leader Bill Shorten has labelled the Turnbull government's third budget "uninspired", saying it favours big business over battlers.
"This is a government who gave billions of dollars to the Commonwealth Bank as a reward, but can't find $360 a year for pensioners grappling with power (bills)," he told ABC TV on Wednesday.
Mr Shorten confirmed Labor would support initial personal income tax cuts - that could deliver some Australians more than $500 a year - but would wait to see more detail of the government's seven-year overhaul of the system before making a decision.
"They want us to have a debate about a possible tax cut in the year 2024. That's two or three elections down the track," he said.
"The government is up to tricky business in this uninspired business that favours big business, not battlers."
Mr Shorten also dismissed the government's return-to-surplus strategy which will bring the budget into balance in 2019-2020, a year earlier than planned.
"This government has been in for five years and they've always said that they're the Superman of economic management." he said.
"They haven't managed to deliver a surplus yet."
Mr Shorten warned any downturn in the trade with China would disrupt the budget strategy.
