China will phase down coal consumption: Xi

China will start phasing down coal use from 2026 as part of its efforts to slash greenhouse gas emissions, President Xi Jinping said at a summit of global leaders, a move that disappointed campaigners hoping for more ambitious pledges.

Xi, speaking via video link to the Leaders Summit on Climate convened by US President Joe Biden, said China was committed to green development and upgrading its coal-dependent energy system, a major source of climate-warming emissions.

"We will strictly limit the increase in coal consumption over the 14th five-year plan period (2021-25) and phase it down in the 15th five-year plan period (2026-30)," he said on Thursday.

Xi's comments mean that China's coal consumption, by far the highest in the world, will reach a peak in 2025 and start to fall thereafter.

Xi already pledged last year to bring China's emissions to a peak before 2030 and make the country "carbon neutral" by 2060.

"China has committed to move from carbon peak to carbon neutrality in a much shorter time span than what many developed countries might take, and that requires hard efforts from China," Xi told the summit.

But after the United States and others set higher targets to slash emissions during the Thursday summit, China was widely expected to deliver more ambitious pledges.

"Unfortunately, there remains a big gap between China's carbon neutrality vision and the reality of what they announced today," said Kevin Rudd, former Australian prime minister and president of the Asia Society, a non-government organisation.

Li Shuo, senior climate adviser for environment group Greenpeace, also said more ambitious measures were still required.

"It is in China's self-interest to announce and implement further plans ahead of COP26," he said, referring to the annual climate meeting scheduled to take place in Glasgow in November.

At a media briefing late on Thursday, Chinese officials stressed that the country's targets were already very onerous.

"China certainly hopes to abandon its overreliance on fossil fuels and in order to meet our 2030 goals, we must address the issue of our coal-fired plants," said Su Wei, deputy Secretary-General of China's state planning agency.

China's energy regulator said earlier on Thursday that it would aim to reduce the share of coal in its total energy mix to less than 56 per cent this year, but it remains one of the only major economies to approve new coal projects.