Australian Treasury boss Ken Henry does not support an altered version of the country’s proposed super profit resource tax, according to Fortescue Metals CEO Andrew Forrest.

The mining magnate allegedly told Forrest the tax would not work if it was altered in any way or form.

The Australian Government is considering making changes to the tax, including removing the 40% guarantee on losses, following a campaign by mining majors which are threatening to move projects offshore.

Henry reportedly told Forrest that if the guarantee is removed the tax would not work.

Forrest told ABC News that banks have also expressed doubt over how the tax will work.

Australian Resources Minister Martin Ferguson recently said the government is willing to negotiate on the profit tax but emphasised the rate of tax will remain unchanged.