Australia's former top climate diplomat has warned China's net-zero emissions target will leave Australia behind, threatening future trade deals and its influence in the Pacific as the Morrison government becomes wedged between the US and China on climate action.

Howard Bamsey, who was Australia's special envoy on climate change during the Rudd government, said the announcement from President Xi Jinping last week had turned the politics of emissions reduction into a sharp economic and diplomatic issue.

Professor Bamsey, who was also Australia's ambassador for the environment under the Howard government, said the new policy "pulls the rug out from under the argument" that Australia's domestic climate goals do not need to accelerate because China was yet to increase its ambitions.

"It's clear now China is accepting a leadership role," he said. "Xi made the announcement. That carries all the weight of the state and party."

The coronavirus has forced this year's United Nations Glasgow Climate Change Conference to be rescheduled to November 2021, turning Australia's international emissions obligations into a major election flashpoint. The earliest month a federal election can be held is August 2021 and voters are expected to go to the polls by the end of next year.

China, which is simultaneously the world's largest polluter and biggest producer of renewable energy, pledged to go carbon neutral by 2060 at the UN General Assembly last week.

Read the full article on The Sydney Morning Herald website, featuring Prof Howard Bamsey