CANBERRA Dec 1 (Reuters) - Australia's government may phase-in the introduction of a controversial mining tax for smaller companies to try and calm opposition to the profits-based tax, a newspaper reported on Wednesday.
The government was looking at offering some concessions above the A$50 million ($47.9 million) tax threshold so smaller miners were not immediately hit with the full impact, the Australian Financial Review said, without citing a source for the information.
And in another move to ease concerns held by some of the fiercest critics of the planned 30 percent tax, the government could also offer a further longer-term concession by indexing the A$50 million hurdle, the paper said.
The government has been in negotiations with mining companies on the shape of the super-profits tax, which it estimates will raise A$7.4 billion ($7.3 billion) in its first two years and help deliver a budget surplus in fiscal 2012/13.
Resources Minister Martin Ferguson last month wrapped up four months of consultation with miners on the tax and government officials said legislation would be ready to go to parliament by May next year, with a draft report ready this month.
In a bid to minimise the chances of a constitutional challenge, the government was drafting legislation to reimburse states for lost resource royalties at a standard capped rate, possibly giving some states a windfall, the paper said.
Mining companies and the government are at loggerheads over whether the tax should credit future rises in state mining royalties, with a cap on the tax and royalties to be applied at an effective tax rate of around 45 percent.
Ferguson has previously said a discussion draft of changes to the tax on coal and iron ore miners would be released in the new year, which would give mining companies another chance to comment on the final shape of the new tax.
But he said the government would not change key details of the Minerals Resource Rent Tax (MRRT) from the deal struck in July with global miners BHP Billiton , Rio Tinto and Xstrata .($1=1.043 Australian Dollars)