Prime Minister Julia Gillard's admission that her government has no plans to change the design of its Minerals Resource Rent Tax has drawn criticism from greens, independents, the opposition and former prime minister Kevin Rudd.
Prime Minister Gillard was asked in parliamentary question time by opposition MPs to comment on media reports that she had written to Independent MP Rob Oakeshott saying the government shared his concerns "about the interaction of state royalties and the minerals resource rent tax".
Ms Gillard explained she was quoting some of the conclusions of a policy transition group which looked last year at how the Minerals Resource Rent Tax (MRRT) would be implemented.
"The government has no plans to change the design of the MRRT," she told parliament.
Treasurer Wayne Swan also reminded the house Australia that had its biggest surge in mining investment in history since the tax was introduced on July 1.
"Every one of those people opposite, when we introduced the MRRT, said it would be the opposite ... that investment would go out the backdoor, as would jobs," he said.
Ms Gillard later drew attention to the coalition's plan to scrap the MRRT.
"Behind this little game they're playing today actually lies some very important questions for the Australian economy," she said.
"Do you believe that Australians are entitled to the benefits of the mineral wealth in their grounds - yes or no?
"We say yes, you say no."
Just hours earlier, former prime minister Kevin Rudd joined a chorus of concern by the Greens and independents about the tax raising only $126 million in its first six months of operation.
Mr Rudd this morning admitted the tax had not collected “any real revenue of any significance”.
He said he was "unfamiliar" with the undertakings given to mining companies by Ms Gillard and Mr Swan when they negotiated the MRRT, but any changes would need to be mindful of these.
"My view has always been pretty basic," Mr Rudd said.
"These resources are owned by the Australian people ... (and) I believe the Australian people deserve, through an appropriate tax mix, an appropriate return.
"No government should ever take a backward step in pursuit of the national interest."
Labor frontbencher Bill Shorten said he was unaware of any government plans to change the mining tax but declined to say whether it is generating enough revenue.
Mr Shorten said he was not “aware of any plans” to change the MRRT, but he did not directly answer questions about whether it was raising enough revenue.
"I’ve always supported having a mining resources rent tax and I believe the one we have is the one we must stick to for the foreseeable future,” he told reporters in Canberra this morning.
Asked whether he blamed Mr Swan for the flaws in the design of the tax, Mr Shorten said: “I wasn’t in the cabinet at the time the taxes were designed. I wasn’t in the expenditure review committee".
Mr Shorten did say he supported the initiatives the MRRT would help fund, including axing the tax on superannuation for the low-paid.
"What I am determined to do is to ... make sure in an election year the government offers a positive vision of the future, the creation of good jobs, the maintenance of fair work relations, and to make sure low-income earners don’t have a new superannuation tax slapped on them,” he said.
Meanwhile, the Australian Chamber of Commerce and Industry (ACCI), which has always opposed the MRRT, has called for the federal government to scrap the controversial mining tax rather than try to fix it.
ACCI chief economist Greg Evans said was an inefficient tax that was not raising any money, nor was it doing the things the government claimed it would do - such as funding a company tax cut.
"We think (the MRRT) should be abolished, there's no point trying to adjust it," he said.
"As they say, you can't make a silk purse out of a sow's ear."
Australian Greens MP Adam Bandt earlier on Tuesday accused Labor of ducking questions on the MRRT.
"The treasurer should have taken responsibility today to outline a timeline for plugging the royalty holes in the mining tax before the upcoming budget," he said in a statement.
Opposition leader Tony Abbott has also weighed in on the debate, labelling the Labor government "a shambles" at a joint parties meeting.
Mr Abbot has vowed to repeal the mining and carbon taxes should the coalition win the next election on 14 September.
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