Finance Minister Mathias Cormann has rejected suggestions now is not the right time to introduce tax cuts for Australian companies.
A $50 billion government plan over 10 years would boost investment, productivity, growth and over time wages, he said.
The planned 25 per cent tax rate - down from 30 per cent for companies with a turnover of more than $2 million - was middle of the pack by international standards.
Labor says the plan will smash the budget when Australia can least afford it.
But Senator Cormann told ABC radio on Monday the tax cuts would not have a net negative impact on the budget.
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Treasurer Scott Morrison said you couldn't squeeze the lemon harder to gain more revenue.
"If you want people to work more hours, which we do and the latest employment figures show that is one of the challenges... the last thing you do is tell the businesses that are employing them that they are going to have to carry a high tax burden," he told ABC radio.
Mr Morrison said the government didn't plan to put the proposed tax cuts to the Senate this year.
"There is a pretty big docket as you know over the next two weeks. We will continue to have that discussion both with the opposition and the crossbenchers," he said.
