Coal-rich Australia unveiled a much-delayed 2050 net zero emissions target Tuesday, in a plan that pointedly dodged thorny details or near-term goals ahead of a landmark UN climate summit.

Widely seen as a climate laggard, Australia is one of the world's largest coal and gas exporters.

For the last eight years, its conservative government has resisted action to reduce emissions, routinely approving new coal projects and peddling scepticism about climate change.

Under domestic and international pressure, Prime Minister Scott Morrison on Tuesday announced a shift in approach and acknowledged the "world is changing".

Australians want policy that "does the right thing on climate change", he said, adding the phenomenon "is real, it's happening. We understand it and we recognise it."

Just how Australia will get to net zero by 2050 carbon emissions remains unclear, with the government refusing to release its modelling.

The plan would invest US$15 billion in low-emission technologies over the next decade, but it also leans heavily on unproven technologies and carbon offsets, which critics deride as an accounting gimmick.

And Morrison was keen to stress he was not dropping long-running support for the country's lucrative fossil fuel industry.

"It will not shut down our coal or gas production or exports," Morrison told a press conference. "It will not cost jobs, not in farming, mining or gas."

While backing away from demands for more ambitious 2030 targets, Morrison said he expects Australia to "meet and beat" the previously agreed goal of reducing greenhouse gas emissions 26-28 percent on 2005 levels.

He said Australia was now projected to cut emissions 30-35 percent by 2030.

"That is something we actually think we are going to achieve. The actions of Australia speak louder than the words about us," he added.

Widely seen as a climate laggard, Australia is one of the world's largest coal and gas exporters
Widely seen as a climate laggard, Australia is one of the world's largest coal and gas exporters AFP / WILLIAM WEST

The announcement comes just days before Morrison departs for next month's United Nations COP26 climate summit in Glasgow.

Australia's reluctance to act had been criticised by close allies such as the United States and Britain, as well as Pacific island neighbours that are highly vulnerable to the impacts of climate change.

The coalition government has also found itself increasingly out of step with Australians' attitudes as they suffered a series of climate-worsened droughts, bushfires and floods.

A 2021 poll by the Lowy Institute think tank found 78 percent of Australians back a 2050 net zero target, while 63 percent support a national ban on new coal mines.

The country's greatest natural tourist drawcard, the Great Barrier Reef, has been badly damaged by waves of mass coral bleaching as ocean temperatures rise.

Mark Kenny, a professor at the Australian Studies Institute in Canberra, said domestic and international pressures had made it "more and more unviable for the coalition to cling to its essentially denialist position".

But Kenny warned Australia's announcement amounted to little more than a shift in rhetoric for the resource-reliant nation.

"This commitment is not significant in reality. I think if the world takes this seriously, they have been sold a pup," he told AFP.

Tuesday's 2050 commitment trails behind more ambitious announcements from Australian states and corporations, including mining giant Rio Tinto.

Australia's major coal customers such as India and China have already indicated they will phase out thermal coal, and technological advances have made the future of metallurgical coal -- used to make steel -- increasingly uncertain.

Ahead of the 12-day Glasgow summit, the UN says more than 130 countries have set or are considering a target of reducing greenhouse gas emissions to net zero by 2050, a target it says is "imperative" to safeguard a livable climate.