"Australia’s internal and global critics on climate change willingly overlook or ignore our achievements,as the facts simply don’t fit the narrative they wish to project about our contribution."

Mr Morrison said on Monday he did not want to set any target yet for emission reductions after 2030,a stance that frustrates environmentalists who believe national leaders should already be pledging deeper cuts.

While Labor went to the election with a promise to cut emissions by 45 per cent by 2050,that is under review in the wake of its election loss.

The UN climate summit ended on Monday with a stated commitment from 77 nations to achieve net zero emissions by 2050,leading UN Secretary-General Antonio Guterres to call the event a"boost in momentum"for global agreement.

The official statement from the UN summit,which Mr Morrison did not attend,included a German commitment to carbon neutrality by 2050,a British promise to double its contribution to climate finance and a statement by China that it would cut its emissions by 12 billion tons annually.

Russia also said it would sign up to the Paris agreement on climate change,the pact US President Donald Trump has chosen to quit.

Arguing his case against unnamed critics,Mr Morrison told the auditorium that Australia was responsible for only 1.3 per cent of global emissions and was on track to"over-achieve"on its 2020 target under the Kyoto Protocol.

Repeating the message he told voters during the election,Mr Morrison said Australia was reducing its emissions by 367 million tonnes more than required to meet the Kyoto target – adding that few developed nations could say the same.

"In 2012,it was estimated Australia would release 693 million tonnes of emissions in 2020,"he said.

"As of 2018,this estimate has fallen to 540 million tonnes."

Mr Morrison said the Australian electricity sector was producing fewer emissions with output 15.7 per cent lower this year than a decade ago.

"While we are a resource rich country,it is important to note that Australia only accounts for around 5.5 per cent of the world’s coal production,"he said.

"Having met and exceeded our Kyoto targets,Australia will meet our Paris commitments as well.

"We are committed to reducing greenhouse gas emissions by 26 to 28 per cent below 2005 levels by 2030."

Mr Morrison said this was credible,fair,responsible and achievable and represented a halving of emissions per person in Australia.

Days afterSwedish activist Greta Thunberg made a scathing speech about the inaction of world leaders,Mr Morrison reprised his remarks to journalists about the danger of"needless anxiety"about climate change.

"We must respect and harness the passion and aspiration of our younger generations,rather than allow others to compound or,worse,facelessly exploit their anxiety for their own agendas,"Mr Morrison said in the closing passages of his UN speech.

"We must similarly not allow their concerns to be dismissed or diminished as this can also increase their anxiety. What parent could do otherwise.

"Our children have a right not just to their future but to their optimism.

"Above all,we should let our kids be kids – teenagers be teenagers – while we work positively together to deliver practical solutions for them and their future."