Labor is expected to support axing the carbon tax, with senior figures - including leader Bill Shorten - now convinced that its case for action on climate change is more easily sold if the politically ''toxic'' tax is abolished.

The Opposition has been wrestling with the repeal of the tax, with some saying it must hold the line to show voters and demoralised supporters it still stands for something. But party leaders have progressed their thinking to consider what the party will put to voters in the lead-up to the next election.

Worried an endless focus on the carbon tax would distract from serious flaws in the Direct Action policy: Labor leader Bill Shorten. Credit:Wayne Hawkins

They argue that Labor proposed to ''terminate'' the tax at the election and to simply block its repeal would allow the government to continue to punish it politically.

Mr Shorten is also worried an endless focus on the carbon tax would distract from serious flaws in the government's $3.2 billion Direct Action policy, which Labor will oppose.