The federal government says it still has not decided whether to sign up to the next phase of the Kyoto Protocol.
Australia is participating in a new round of UN climate negotiations that kicked off in the German city of Bonn this week.
Green groups are watching to see whether Australia will use the meeting to signal support for a second Kyoto commitment period.
The first commitment period is due to end this year.
Climate Change Minister Greg Combet says the government has not made a decision.
“The government is considering the international settings following last year’s Durban climate change conference and their implications for carbon pricing in Australia,” a spokesperson for Mr Combet said.
“In addition, some important aspects of the second commitment period have not yet been concluded.
“These outcomes will inform Australia’s decision.”
Oxfam Australia’s climate spokeswoman Kelly Dent said Australia should sign up without delay.
“It seems hard to believe that Australia would contemplate a flight from the treaty, just at the moment when the government has secured a price on carbon pollution and a mechanism to reduce greenhouse gases,” she said.