As the Rio+20 negotiations conclude, Australians will be horrified at the world's failure to act and at Australia's push to water down the mining sections of the agreement, said the Australian Greens today.

"The Prime Minister tonight expressed satisfaction with the outcomes of Rio+20, despite widespread condemnation by environment and youth groups, the community and many of the participants, at the failure to commit to any new goals or to produce anything tangible," said Australian Greens environment spokesperson, Senator Larissa Waters.

"It is unclear whether Australia even pushed to re-open the text of this weak agreement once the Prime Minister arrived, or if she was content to see the 20th anniversary of the world's most important sustainable development conference wasted.

"The power of Australian mining barons was on full display this week, as our diplomats pushed for so-called 'sustainable' mining, and watered down the fossil fuel subsidies text to remove timeframes and promote 'efficient' subsidies to wealthy mining giants.

"There is no such thing as an efficient fossil fuel subsidy, and multi-billion dollar tax breaks and handouts are subsidies – so the Prime Minister's comments that 'Australia is not in the business of fossil fuel subsidies' must now result in the cancellation of the $7.3 billion in subsidies paid to big polluters annually.

"The failure of any new commitments at Rio+20 makes strong domestic action all the more necessary to tackle the world's environmental crises. The Prime Minister should start by demanding Minister Burke strengthen, not weaken, our environmental laws," said Senator Waters.

Senator Waters self-funded her trip to Rio for the Rio+20 conference.