Developed countries today agreed to negotiate slashing greenhouse gas emissions by up to 40 per cent over the next decade in a last-gasp decision at the Bali climate change conference.



To applause from delegates, Australian negotiators "strongly supported" the controversial proposal for cuts of between 25 and 40 per cent by 2020 - leading to its adoption by consensus by the conference.



The move came during the Ad-hoc Working Group (AWG) deliberations which followed the formal end to the fortnight-long United Nations climate change conference.



The conference adopted a roadmap for further negotiations on slashing greenhouse gas emissions, but it fell short of adopting specific targets, referring only to scientific studies that cite the need for cuts in the 25 to 40 per cent range.



Although the AWG decision does not set a binding target, it commits developed nations to negotiate appropriate targets within the 25 to 40 per cent range in the two-year post-Kyoto Protocol talks, agreed to today by all countries.



Environmental groups were overjoyed at the breakthrough, which for the first time sets a goal for short-term emissions reductions for all developed nations, including Australia and the United States.



"It's great to see Australia changing its position and starting to take a more progressive role in international climate negotiations," Greenpeace campaign director Steve Campbell said tonight.



"We had concerns that Australia would continue to play a wrecker role in Bali but at the very end Australia did the right thing."



Climate Institute chief executive John Connor said victory had been snatched from the jaws of defeat at the talks.



"These [targets] are not binding but they are an important scientific reference point," he told AAP from Bali tonight.



"What we've seen here is Australian leadership in Australia's national interest because Australia is one of the countries most at risk from climate change."



Australian Conservation Foundation executive director Don Henry said Australia's ratification of the Kyoto Protocol and Prime Minister Kevin Rudd's presence in Bali had played a part in shaping the outcome.



He said Australia would need to move into a strong leadership position to ensure successful negotiations.



"We've got a roadmap that recognises the science, now comes two years of crucial negotiations on which the very future of our children depends," Mr Henry said in a statement.



"We will need continued strong people power in Australia and around the world to ensure our governments act with the urgency and scale needed to get on top of climate change before it is too late."



Earlier, an exhausted Climate Change Minister Penny Wong said a night of tough negotiations was worth it to help forge the international agreement.



Emotional delegates cheered and clapped when the US caved in late this afternoon and agreed to support the Bali roadmap.



The US concession - 14 hours after the initial deadline passed - came after two weeks of talks and a day of high drama, in which conference head Yvo de Boer stormed out in tears and American delegates were booed and jeered.



"We will go forward and join consensus," US lead negotiator Paula Dobriansky told the 190-nation meeting.



The breakthrough came after United Nations Secretary-General Ban Ki-moon and Indonesian President Susilo Bambang Yudhoyono took the extraordinary step of addressing the delegates, urging them to compromise in the interests of the world.



Mr de Boer, the executive secretary of the UN Framework Convention on Climate Change (UNFCCC), was given a standing ovation after he returned to the hall for the conclusion of the gruelling negotiations.



Delegates agreed to launch talks on a new global warming pact to succeed the Kyoto Protocol in 2012, with a decision to be reached at a meeting in Copenhagen in late 2009.



Senator Wong, Australia's lead negotiator, co-chaired a crucial meeting into the early hours of this morning which brokered a truce between the US and the European Union over the interim targets.



She conceded there had been some feisty discussions but said it had helped win an overall agreement.



"We made some very positive progress last night and we're very glad that that yielded some result today," Senator Wong told reporters.



"Obviously there were some very different positions in the room.



"These are hard negotiations and this was a hard-won consensus. So I'm sure you can infer from that what at times things were like in the room.



"But this was a negotiation where, whatever people thought about the detail, there was a genuine willingness for compromise, a genuine willingness to negotiate, and a strong commitment to forging an agreement, a strong commitment to coming together to make a plan so that we can move forward."



Mr Rudd, who spent three days at the conference earlier in the week, ordered the Australian negotiators to do whatever they could to ensure the talks wound up with a commitment from all countries to launch formal negotiations with a 2009 deadline.



The major sticking point between the US and the EU was a plan, supported by developing nations and the EU, to include interim targets for developed nations to slash emissions by between 25 and 40 per cent by 2020 to immediately tackle global warming.



AAP