Though the ETS is scheduled to come up for the senate vote next month, it now looks set to be knocked down, following a statement by Turnbull that he would move to defer the vote until after the international climate change negotiations in Copenhagen in December.

If the ETS were to be defeated in the senate twice in a three-month period, it would result in a double dissolution, triggering an election. It would be the first double dissolution since 1987, when the Hawke government was returned to power, but without a majority in the senate, following two defeats of the Australia Card Bill.

Turnbull said it was premature to lock Australia into an ETS before the international position was clear, particularly if it would be out of step with United States ETS legislation, which is yet to be finalised.

"It is clear that the emerging Obama plan will offer 100 per cent protection for US export and import-competing industries until 2025. The Government's current plan would, therefore, leave many of Australia's most successful industries (and largest employers and taxpayers) at a crippling disadvantage," he said.

However, Federal Minister for Climate Change Penny Wong has accused Turnbull of backtracking on his earlier stated position, which was to push the ETS forward quickly. "Less than 12 months ago, Mr Turnbull said he wanted to 'Move on emissions trading come what may' and emphasised that his position was 'Not conditional on international action.' Today, Mr Turnbull has been forced by the party room again to delay a decision on climate change.

"If everyone took Mr Turnbull's approach, the world would not secure a global agreement," she said.

Wong also denied Turnbull's claim that the proposed US bill would provide more assistance to emissions-intensive industries than Australia's proposed scheme.

"The Australian CPRS provides around 25 per cent of permits free to emissions-intensive trade-exposed industries, compared with just 15 per cent under the current US bill," he said.

Turnbull has confirmed that the Opposition would offer the Government bipartisan support for its proposed carbon emissions target going into the Copenhagen negotiations.

The targets currently stand at unconditional cuts of 5 per cent on 2000 levels by 2020, and cuts of 25 per cent if an international agreement is reached.

However, Wong described this compromise as "a con". "[Turnbull] is offering no plan and no certainty on how to deliver those targets," she said. "He is exposing the Australian economy to unlimited risk by not putting forward any plan to deliver those targets."

- Zoe Lyon