The billionaire said he would change the top rate tax proposal to 33 per cent from 25 per cent during a speech in Detroit about “economic renewal”.
Promising a tax overhaul, he said that he would streamline the taxation process and cut tax brackets from seven to three, with bands at 12 per cent, 25 per cent and 33 per cent. Currently the top rate of tax is set at 39.6 per cent.
He added: "I am going to cut regulations massively, massively."
Speaking on corporation tax, Trump said: “Under my plan, no American company will pay more than 15 per cent of their business income in taxes. In other words we are reducing your taxes from 35 per cent to 15 per cent,” said Trump. "In the days ahead we will provide more details on this plan."
However, Trump failed to mention how he would fund such cuts, worrying economists that the deficit could soar. He has called for a huge increase in infrastructure spending that would be financed by new debt, though details are at current unclear.
Asked by Fox last week how much he would spend on infrastructure, he said: “Well, I would say at least double her numbers, and you're going to really need more than that. We have bridges that are falling down. I don't know if you've seen the warning charts, but we have many, many bridges that are in danger of falling.”
Pressed on how it would be paid for, Trump said: “We'll get a fund. We'll make a phenomenal deal with the low interest rates."
He added that the finance will be provided by: “People, investors. People would put money into the fund. The citizens would put money into the fund,” and adding that he will use “infrastructure bonds from the country, from the United States.”
With taxes falling and the spending to be debt-financed, questions have been raised about his commitment to reducing the national debt.
Still, during the speech in Detroit, Trump pointed to how national debt had risen under Barack Obama and how the "Obama-Clinton agenda of tax, spend and regulate has created a silent nation of jobless Americans."
The speech was an attempt by Trump to reassure Republicans who were nervous of his agenda in handling the economy.
Trump also said he will immediately cancel all illegal and overreaching executive orders, and said he would implement a full tax deduction for the cost of childcare.
Rival Hillary Clinton is still the frontrunner with pollsters and bookies alike, but Trump has defied greater odds than those confronting him now to simply gain the Republican nomination.