Govt confident of bedding down mining tax

Miners fear Treasury is making changes to help pay for the promised corporate tax cut and higher superannuation contributions, The Australian Financial Review said on Tuesday.

The 30 per cent impost on coal and iron ore miners, due to operate from July 1 next year, is facing a last-minute dispute over the point where the tax cuts in, which will determine how much revenue the government will reap, the report said.

The tax has been forecast to raise $11.1 billion in the three years to 2015.

Ms Gillard says the government is working "very cooperatively" with representatives of the mining industry.

"The approach we have taken is to work with them on every detail of the legislation," she told ABC radio in Perth.

"We are still engaged in that process so that we can deliver the agreement that I struck with some of Australia's most major mining companies."

Ms Gillard negotiated a deal with BHP Billiton, Rio Tinto and Xstrata last year to replace the highly controversial resource super-profits tax with the MRRT.

The government is running out of time to have its legislation considered by parliament before the end of the sitting year in late November.

A spokesman for Treasurer Wayne Swan said the government had consulted broadly with industry on the tax.

"The government ... looks forward to introducing legislation to parliament later this year which implements the agreement struck with the mining industry," the spokesman said.

"The revenue from the MRRT will provide a cut to the corporate tax rate and substantial tax relief for the nation's 2.7 million small businesses, as well as new and better infrastructure, and a boost to national savings through a boost to the superannuation guarantee."

Australian Greens leader Bob Brown said the government should not bow to miners any further.

Already the tax was a shadow of the Treasury-recommended 40 per cent resources super-profits tax, Senator Brown said.

"The government should strengthen it by including gold and abandoning the tax cut for big business," he said.

Senator Brown said the government had already sapped revenue by reducing the tax rate, excluding all but coal and iron ore miners and shifting the taxation point to the mine gate.

"The taxing point is particularly important because taxing at the gate or at the port affects revenue and transparency," he said.

Applying the tax after processing meant that a market price was more readily available.

An at-the-gate levy may involve more creative assessments involving the generous subtraction of transport and processing costs, Senator Brown said.

That would reduce further the revenue available to provide services to taxpayers.