Grant Shapps has pledged to cut income tax straight away if he becomes the next prime minister.
The transport secretary said he would introduce an “emergency budget” within days of taking office to to reduce the basic rate by a penny in the pound.
He also vowed to scrap the planned rise in corporation tax as he sought to underline his tax-cutting credentials.
In addition, Shapps said a government led by him would spend three per cent of GDP on defence - up from around two per cent at present.
He said he would pay for all of those multi-billion pound pledges by cutting public spending - but failed to identify where the axe would fall.
Former chancellor - and the early favourite to be the next Tory leader - Rishi Sunak announced at the budget in April that he wanted to cut income tax by 1p before the next election, which is due in 2024.
But speaking on Sky News’s Sophy Ridge On Sunday, Shapps said: “If I become prime minister we’ll have an emergency budget, we’ll introduce that immediately.”
He said he also wants to “freeze” Sunak’s proposed increase in corporation tax, adding: “That is a tax which will not go up.”
Shapps said: “I believe in a lower tax, lower regulation, cut the red tape economy, where… the government essentially actually lowers the barriers for individuals and businesses to achieve the best possible things they can in their own lives.
“And I think the role of the government is to help with that. But sometimes that means reducing taxes, it means being able to reduce red tape, make it easier to deal with government, get on with your life, start a business, bring up a family, bring up children.”