The prime minister has told business leaders the government might reach its 2030 target of reducing emissions by 26 to 28 per cent below 2005 levels through technology.

This would avoid having to use Kyoto credits amassed before 2020, which the government has been criticised at home and abroad for not ruling out.

"I have always said we will only use carryover to the extent required. My ambition is that we will not need them and we are working to this as our goal, consistent with our record of over-delivering," Mr Morrison said.

"I am confident our policies will get this job done."

The prime minister said he would have more to say before the end of the year "as we update our emissions projections to take into account new policies and measures".

Mr Morrison again pledged to reach net zero emissions as quickly as possible, but was silent on joining Australia's major trading partners in setting a 2050 deadline.

"I won't make a commitment on behalf of the Australian people unless I can tell them how we will achieve it, and what this will cost," he said.

"In this respect, Australia truly does stand out.

"We are actively working through these considerations right now, including how our practical, technology-based approach can get us there."

Meanwhile, young people from around the world are forging ahead with an online climate summit in the hopes of stamping strong targets into law.

The United Nations Climate Change Conference, known as COP26, was due to be held in Glasgow this month but has been postponed until next year.

This has prompted more than 350 youth delegates from over 140 countries to take part in a virtual forum.

The summit's final statement will be developed into a formal treaty and handed to governments to consider adopting into law.

Australia's five-person delegation includes Adelaide student Tom Webster, who is raising awareness of Indigenous bushfire prevention methods, the Adani coal mine and rising sea levels in the Torres Strait.

Once the treaty is complete the Australian team will hand it to environment and energy ministers across all levels of government.

The 15-year-old told AAP he hopes for climate solutions that will ensure a safe future for all and keep the world below two degrees warming before the end of the century.

"As a young person, climate policies and environmental policies will be one of the crucial things that I will be looking at when I decide who to vote for, once I turn 18."

Australia's statement to the event will focus on last summer's bushfire season and the climate impacts on coral reefs.

The delegates will also promote the transition to renewable energy to achieve net zero emissions by 2050, drive investment and create jobs for fossil fuel workers.

Australian Associated Press