Shadow assistant treasurer Andrew Leigh says Labor will support scrapping the carbon tax but insists it needs to be replaced with an emissions trading scheme.

"We said we would scrap the carbon tax, the fixed price period, and move straight to a floating emissions trading scheme," Dr Leigh told Sky News on Tuesday.

"That's something that we will be happy to vote for on the floor of parliament."

This is consistent with the policy Kevin Rudd took to last month's election, he said.

But he clarified there would still have to be discussions in shadow cabinet and caucus about the party's final position on the government legislation.

Parliamentary secretary for environment Simon Birmingham said he wasn't convinced Labor had heeded the electorate's message that "they want to see the carbon tax gone - gone in its entirety, not just gone for a year".

"We will be introducing legislation to parliament that repeals the carbon tax in its entirety from 1 July next year forever more," he said.

Dr Leigh said the lesson Labor had learned was from 2010.

"We were seen to walk away from carbon pricing," he said. "I think it would be a mistake for us to do that again."

He says he doesn't believe the coalition's direct action policy will work to halt climate change.

Reported plans to attach direct action to the budget bills was "a classic Tea Party trick" used in the US Congress, to force Labor to vote for the "whacky" plan or make the whole budget fall.