The Federal Government has flatly dismissed efforts by the Greens to increase budget revenue from the mining tax.
The Greens have used their 20th national conference in Sydney to spruik their economic agenda.
Greens leader Christine Milne urged the Federal Government to delay the budget surplus.
They have also commissioned costings data which reveal that a 40 per cent increase in the Minerals Resource Rent Tax would increase budget revenue by $26 billion over four years.
"If we invested it wisely we could lift Newstart, we could make sure we ploughed that money into education," Ms Milne said.
But Prime Minister Julia Gillard says she will not be heeding the Greens advice.
"We have implemented the mining tax that we believe is the right one for the nation," she said.
Senator Milne says Ms Gillard's refusal proves she has caved in to the mining industry.
"At the moment the mining tax is securing zero, it's projected to secure $9 billion, well we could take that out to $26 billion," she said.
"So this goes to the heart of the Prime Minister's claims to be the great negotiator, she negotiated a tax that has resulted in zero in the first three months." The Greens conference also canvassed the party's core policies towards the environment, Indigenous recognition and same-sex marriage.