SOME of the world's biggest carbon-emitting nations have urged Australia explain how its climate-change polices will achieve a 5% reduction in emissions by 2020.
A series of questions has been put to Australia through the United Nations, from countries including big-emitting China, Brazil and the United States.
The questions cover the gamut of the Abbott government's direct action policy, which economists doubt can achieve the promised reductions, despite the government maintaining it will.
It comes as other nations begin preparing for the latest round of global climate-change talks and setting of new carbon emission reduction targets, in Paris later this year.
Climate Institute chief executive John Connor said while the government "to its credit" had not abolished the target, China and other larger nations had begun tightening targets, and were asking what Australia's plans were.
Mr Connor said it was an "opening salvo of scrutiny" for Australia's current climate-change policies.
Environment Minister Greg Hunt has guaranteed repeatedly Australia would reach the target by 2020, on the back of a $2.5 billion fund to pay polluters to stop emitting.
But he has not yet detailed what plans Australia will put in place for emissions reductions after 2020, when the existing agreement will expire.
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