The "Global Coal to Clean Power Transition Statement" commits signatories to both phase out coal power and end support for new coal power stations.
It already has the signatures of Vietnam - a mooted, major destination for Australian coal - and Poland - a country that ranks ninth in the world for coal consumption.
Climate Councillor Professor Will Steffen called the statement "coal's curtain call".
"It is a major global commitment and the world's second largest exporter of thermal coal, Australia, is nowhere in sight," he said.
"First, we refused to join more than 100 other countries in the global methane pledge, and now this. Australia is so out of step and out of touch with the rest of the world, and that's going to harm our economy, climate and future prosperity."
The UK government says alongside pledges by major banks to end coal - and earlier commitments from China, Japan, Korea and G20 countries to end overseas finance for coal by the end of 2021 - this effectively ends international public finance for additional unabated coal power.
"Fossil fuels like coal have got to go, because they are accelerating global warming, which is worsening extreme weather events like the Black Summer bushfires that harm Australians," Steffen said.
"We have known about the risks, impacts and costs of climate change for some time, but it seems the prosperity and wellbeing of Australians is once again being ignored in favour of short-term profits for coal and gas corporations."
"Whether Australia likes it or not, the world is moving toward net zero and that has serious ramifications for our country, particularly for communities and sectors that have traditionally relied on fossil fuels."
The Climate Council recommends Australia reduce its emissions by 75% below 2005 levels by 2030 and achieve net zero by 2035.
This is based on what it calls rigorous scientific risk assessments.
Australia is the world's second largest export of thermal coal - the kind used in power stations - and produces 20% of the total coal traded internationally.
The top five countries that Australia exports coal to are: Japan (43%), South Korea (16%), Taiwan (13%), India (7%) and China (3%).
