Prime Minister Scott Morrison has again refused to commit to a target of net zero emissions by 2050, after an international "code red" warning on climate change was issued by global leaders.

"I won't be signing a blank cheque on behalf of Australians to targets without plans," Mr Morrison said.

"Blank cheque commitments you always end up paying for, and you always end up paying in higher taxes."

The United Nations' Intergovernmental Panel on Climate Change (IPCC) has warned the Earth will warm by more than 1.5 degrees Celsius within the decade, causing rising sea levels and more frequent and devastating natural disasters, unless drastic action is taken to reduce carbon dioxide emissions.

UK Prime Minister Boris Johnson has called the warning a "wake-up call" for world leaders to act.

But climate policy has become highly politicised in Australia and the Prime Minister's biggest obstacle to adopting a net zero target is the junior Coalition partner, the Nationals.

Within the Liberal Party though, there is a growing number of MPs speaking out in favour of a 2050 target, including West Australian Liberal Celia Hammond.

When asked if Mr Morrison would ultimately adopt the target, she said: "I, of course, think that we will, I do, yes,".

"It makes economic sense. It makes environmental sense," she told the ABC.

"And I think people also want to move on from the days of the climate wars." 

Instead, the Prime Minister has previously said Australia will "preferably" reach that target by 2050.

Mr Morrison said Australia's response would be led by technological change.

"World history teaches one thing: technology changes everything," Mr Morrison said.

"That is why our approach is technology and not taxes to solving this problem."

The government has previously said it will invest in hydrogen technology and "carbon capture" technologies as part of its efforts to reduce Australia's emissions.

Technology to remove carbon dioxide from the atmosphere has not yet been proven to work at scale.

Mr Morrison said he would provide an update on what the government expected to achieve in emissions reductions by 2030 ahead of a major international climate conference in Glasgow, Scotland later this year.

Speaking on Sky News, Labor deputy leader Richard Marles said the government needed to commit to a net zero by 2050 target.

"It's really important that this government actually resolves its internal issues and starts acting with intent in relation to action on climate change," Mr Marles said.

"To have the government party room full of a whole lot of people who are essentially denying the science of climate change in 2021, is genuinely unbelievable."

Climate protester 'foolishness' condemned by PM

Mr Morrison also took aim at climate protesters who vandalised Parliament House earlier today.

"I don't associate in any way shape or form that foolishness with the good-hearted nature of Australians who care deeply about this issue, as I do," he said.

"Action will be taken against those who have committed those offences in our capital today, as they should, and I think Australians — regardless of their position on this issue — would agree with that."

Eight protesters were arrested at Parliament House and the Lodge this morning for property damage and other offences.

Police said at both locations protesters had sprayed graffiti onto walls and that people had glued themselves to the forecourt at Parliament House.