Former finance minister Mathias Cormann, once a fierce critic of carbon pricing mechanisms to reduce greenhouse gas emissions, has issued a call to governments around the world to better coordinate carbon price policies.
Now the secretary-general of the Organisation for Economic Co-operation and Development (OECD), Mr Cormann appealed to world leaders ahead of the COP26 summit in Glasgow to ensure the pricing of emissions is adopted in a way that is "both effective and fair".
"The aim is to help manage and ensure the net zero transition in a way that is both effective and fair," he said.
"Effective in that efforts in jurisdictions actually help to reduce global emissions and don't just shift them to other parts of the world.
"And fair - in that every country carries an appropriate, proportionate and verifiable share of the burden."
Mr Cormann is Australia's longest-serving finance minister which he remained for seven years until 2020.
During that period, he declared a strong opposition against carbon pricing mechanisms. In 2011, Mr Cormann told federal parliament the Gillard government's plan for a carbon tax is "a very expensive hoax" that will "push up the cost of living".
In tweets that same year, he described carbon taxes as “an act of economic self-harm which does nothing to help global emissions”.
As a senior member of the Abbott government, he supported the repeal of the Gillard government's carbon tax in 2014.
Australia does not have an explicit carbon-pricing scheme today.
In a message addressed to G20 leaders including Australian Prime Minister Scott Morrison - who are meeting in Rome ahead of COP26 - Mr Cormann said ambitious climate change policy needs to be the number one priority.
"Let's make ambitious and effective global action on climate change our number one priority," he said.
A report released this week by the OECD makes the case for carbon pricing mechanisms - such as carbon taxes and emissions trading schemes - to be used to transition to net zero emissions and to support a "green recovery" post the COVID-19 pandemic.
In a statement, Mr Cormann said better coordination across nations is needed to avoid "carbon leakage and trade distortions".
"We need a globally more coherent approach which enables countries to lift their ambition and effort to the level required to meet global net zero by 2050, with every country carrying an appropriate and fair share of the burden while avoiding carbon leakage and trade distortions," he said.
"Carbon prices and equivalent measures need to become significantly more stringent, and globally better coordinated, to properly reflect the cost of emissions to the planet and put us on the path to genuinely meet the Paris Agreement climate goals."
In 2019, he defended the lack of a carbon tax in the federal government's policy.
"Our government is committed to effective action on climate change in a way that is economically responsible."
The OECD report "" found that G20 economies account for around 80 per cent of global greenhouse gas emissions. It noted that the adoption of a carbon tax in Mexico and South Africa, along with emission trading schemes in China, Canada and Germany had lifted the coverage of emissions that had been subject to pricing policies.
In 2021, G20 economies priced 49 per cent of CO2 emissions from energy use, up from 37 per cent in 2018.
The report found that Australia had priced just 22.4 per cent of national CO2 emissions from energy use in 2021, a level "unchanged since 2018".
The report will be presented during COP26 on 3 November.
Mr Morrison will present Australia's climate policy target of net zero emissions by 2050, after lengthy negotiations with the Liberal government's coalition partner, the National Party.
He has said Australia's 2030 target remains 26-28 per cent below 2005 levels, although the federal government estimates it will achieve between 30 and 35 per cent by that date.
