For the first time in several years Australia will not be represented by a minister at a major round of international climate change negotiations, with Greg Combet set to miss talks in Doha starting next week.
Mr Combet said he was not attending because after a long year bedding down Australia's carbon price he would be spending some time working on issues in his manufacturing portfolio.
''I am going to spend a bit of time on my other portfolio area. We are able to do that because we have carbon price implemented, European Union emissions trading scheme linking agreed, and Kyoto protocol second commitment period all done,'' he said.
The government will be represented by the Parliamentary Secretary for Climate Change, Mark Dreyfus, who has attended most of the climate change negotiations this year on behalf of the government.
Mr Combet said: ''Mark Dreyfus is very capable, he is the cabinet secretary, he is my assistant minister, and he has been doing the pre-conference of parties meetings.''
Opposition climate action spokesman Greg Hunt said Mr Combet's non-attendance appeared ''an overdue concession to the reality nothing is expected out of the Doha conference''.
Greens leader Christine Milne will also miss the talks after attending the previous conferences over most of the last decade.
Meanwhile, a report released ahead of the talks in Qatar says greenhouse gas concentrations in the atmosphere have risen to their highest levels on record.
In its annual greenhouse gas bulletin released on Tuesday, the World Meteorological Organisation says atmospheric concentrations of carbon dioxide have risen to 390.9 parts per million in the atmosphere.
Atmospheric concentrations of more potent greenhouse gases nitrous oxide and methane were also rising.
The organisation said that the warming effect, which is due to greenhouse gases in the atmosphere, increased 30 per cent between 1990 and 2011.