Labor's proposed emissions trading scheme does not equate to a new carbon tax and the Abbott government assertion that its emissions cuts are akin to the United States are incorrect, according to the government's own climate change advisers.

Climate Change Authority chair Bernie Fraser issued the strong statement late on Friday, responding to the government's post-2020 emissions targets announced this week.

The government intends to reduce the amount of greenhouse gas released into the atmosphere by 26-28 per cent by 2030, based on 2005 levels.

On Tuesday, Prime Minister Tony Abbott told Parliament that Australia's target compares well with other developed countries and was "the same as the United States", despite that nation promising to meet its cuts five years earlier. He stood by the comments after Labor called on him to apologise.