Australian Greens Leader Christine Milne.
Australian Greens Leader Christine Milne. Contributed

Senator Milne leads call for expansion of nation's mining tax

THE Greens have renewed calls to expand the mining tax after it was revealed the measure would deliver $1.2 billion less than Treasury's October forecast.

Analysis from the Parliamentary Budget Office showed the Mineral Resource Rent Tax was on track to raise just $800 million in the current financial year.

Over the next four years the PBO, which conducted the analysis in March, estimated the mining tax would generate $6.4 billion - $3.5 billion less than was forecast in the Mid Year Economic and Fiscal Outlook.

The PBO cited weaker commodity prices for the dramatic drop in MRRT revenue.

But the Greens say a range of measures it had costed by the PBO would not only plug holes in the mining tax, but raise an additional $26 billion over the next four years.

The Greens want the tax rate lifted from 25% to 40% as well as including all minerals in the MRRT, which the PBO predicts would add $18 billion and $2.8 billion to the government's coffers respectively over the next four years.

Greens Leader Christine Milne said hers was the only party with the "guts to stand up to the mining companies".

"It's time Julia Gillard explained why everything except the big miners is on the table for revenue raising," Senator Milne said.

"It's ludicrous to think we can raise the revenue we need to plug the ballooning deficit with more and more cuts to the community when Rio Tinto and BHP and Gina Rinehart made multi-billion dollar profits this year.

"It's time Julia Gillard and Tony Abbott stopped asking the community to brace for tough choices, cutting funding to universities, single parents, and foreign aid, and stood up to the big mining companies that can and should pay more."

A Senate inquiry into the MRRT was expected to release its report after 4pm on Monday.