Treasurer Scott Morrison has made a fresh bid to secure business tax cuts, arguing a further delay will hold back pay rises for Australian workers.
The government has so far legislated a tax cut for businesses with turnovers of up to $50 million, leaving the remainder on a rate of 30 per cent.
But it is fighting an uphill battle to convince Senate crossbenchers to pass the rest of the plan, which will see the tax rate for all corporate entities drop to 27.5 per cent by 2024/25 and eventually to 25 per cent by 2026/27.
Mr Morrison told the Citibank forum in Sydney on Friday globally uncompetitive tax rates are not only a drag on economic growth but made it harder for businesses to pass on better wages.
"It holds back the pay rise that Australians have been looking for, it delays it even further," Mr Morrison said.
"Australian workers will continue to be short-changed on wages by Labor and our parliament's insistence that businesses pay governments more rather than enabling them to pay their workers more."
Amid reports the government may dump the plan in favour of personal income tax cuts, Mr Morrison said it was not right to "go to water the first time that someone makes a criticism of your policy".
"This government will not relent to that," he said.
Finance Minister Mathias Cormann earlier said the government would fight for company tax cuts at the next election if they are torpedoed in the Senate.
"They were very necessary at the last election - they'll be even more important by the time of the next election," he told Sky News.
Deputy Labor leader Tanya Plibersek said the government was ripping funding from universities to pay for tax cuts.
"What kind of prime minister wants to make it easier for big business to pay less tax, but harder to for people to go to uni?" Ms Plibersek said.