The federal government insists it is on track to meet its 2020 emissions-reduction target even without a carbon tax.
The government is using new figures from the National Greenhouse Gas Inventory to argue Labor's carbon tax was an ineffective policy to reduce emissions.
In its first year of operation, emissions rose from 566.4 million tonnes in 2011-12 to 567.1mt in 2012-13, the first rise in five years.
They resumed their decline in 2013-14, falling to 563.5mt.
The 2.9mt decline over the life of the carbon tax compared with average falls of 10mt a year before its introduction.
Environment Minister Greg Hunt said there was no denying that during the carbon tax era, emissions fell at one-sixth the rate of the pre-carbon tax era.
But he insists the figures also show Australia is on track to achieve the 2020 reduction target but without the cost of a "massively expensive" carbon tax.
"We are one of the small number of countries who have actually not just achieved our first round of Kyoto goals, but well and truly surpassed what we committed internationally," he told ABC radio on Monday.
The government's carbon-tax alternative - an emissions reduction fund - begins operation in 2015.
What Australia commits to post-2020 is still up in the air, as is a possible higher 2020 reduction target in line with increased global action before then.
Mr Hunt says the government will wait for the next major climate conference in Paris at the end of 2015 before making a decision on both targets.
