Kevin Rudd says Australia faces export taxes from trading partners if it doesn't act soon on setting new and more ambitious emissions targets.
Mr Rudd's comment at the National Press Club came as the US and UK issued a joint statement in London declaring a commitment to achieving net zero greenhouse gas emissions no later than 2050.
The former Labor prime minister said it should not be a matter of Australia being "dragged kicking and screaming" to set the same target as the US, UK, South Korea and other advanced economies.
"If we don't do it, we'll face very soon border adjustment taxes - from the European Union for being climate change laggards - on our exports," he said.
"The second thing that we need to do is bring about a new nationally determined commitment for the 2030s ... if you go for a mid-century carbon neutrality target of 2050, frankly you've got to have a credible trajectory from where you peak at carbon in the 2020s."
Following a meeting between US climate envoy John Kerry, British leader Boris Johnson and COP26 climate summit president-designate Alok Sharma in London, a statement was issued resolving all nations to "strengthen climate ambition".
"Our countries are fully committed to achieving net zero greenhouse gas emissions no later than 2050," the statement said.
"We urge all countries to take the steps needed to keep a 1.5 degree C temperature limit within reach, including through ambitious nationally determined contributions and long-term strategies to cut emissions and reach net zero."
The issue will also be on the agenda for the G7 leaders summit, which Prime Minister Scott Morrison has been invited to attend in the UK in June.
Fortescue Metals Group boss Elizabeth Gaines told a business summit in Sydney the transition to renewable energy must be sped up.
"A lot of governments and whole industries have committed to net zero emissions by 2050," she told the Australian Financial Review summit.
"But if we want to align with the Paris agreement, 2050 will be too late."
She said overseas investors, especially in Europe, understood the need for the faster push to renewables.
