The federal government could struggle to get its carbon tax through parliament.
The government wants a carbon price from July 2012, and has promised to compensate households for increased energy costs on a permanent basis.
Key independent MP Tony Windsor has told the ABC that while climate action will benefit the bush, he won't "vote for something that does nothing".
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"There is no carbon tax, there may not be a carbon tax," he said.
"The prime minister doesn't have the numbers, as I understand it at the moment.
"I have a vote, others do as well, so you can never guarantee something before it gets through a minority parliament," Mr Windsor said.
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But Prime Minister Julia Gillard, says Mr Windsor has been "perfectly consistent" in his approach to the carbon price debate.
She says Mr Windsor, who sits on the multi-party climate change committee, does believe climate change is real and that pricing carbon is the best way and an important way of tackling climate change.
Ms Gillard has told ABC radio he's going to look at the legislative package and wait to the end and then judge it.
She says Labor remains determined to introduce a carbon tax from mid-2012 followed by an emissions trading scheme.
