Tony Abbott has pledged to repeal the carbon tax if elected. Picture: Ray Strange. Source: The Daily Telegraph

Mr Abbott has also revealed he would immediately halt any further grants under the $10 billion Clean Energy Fund.

With the government’s carbon tax due to come into effect on Sunday, Mr Abbott has written an open letter to newspapers, outlining his plans to repeal the tax if elected.

The first step would be to order the Clean Energy Finance Corporation to cease making any grants or funding decisions as soon as an election was called in line with the caretaker provisions.

If the Coalition was elected, on day one he would direct the Department of Prime Minister and Cabinet to draft legislation to dump the tax.

It would be approved by cabinet within 30 days and would be presented to parliament on the first sitting day.

Many business and industry leaders are sceptical about the decision to repeal the tax, arguing that many had already made investment decisions around it and that it would lead to more uncertainty over the next year.

But unless a Coalition government won control of the senate, it would not be able to get any legislation to repeal passed through the parliament.

The government has also argued that Mr Abbott would be caught out scaring people over the impacts of the tax after July 1, claiming the sky would not fall in with increased prices.

“To oppose the mandate of a government elected on a platform of abolishing the carbon tax would be as reprehensible as the Gillard government’s action to introduce the carbon tax without a mandate from the people,” Mr Abbott said in his letter.

Labor MPs have said there would be no reversal of the tax, even if it lost government over the issue.

Mr Abbott said he would also direct the Department of Environment, if elected, to immediately implement the Coalition’s direct action plan, which has been derided by the government and the Greens.