Vice-Premier Ma Kai announced on Tuesday from Paris that China will launch a national carbon-trading system "in the coming days" but he said a national carbon market will need to be set up step-by-step.

"I am announcing that China will be launching a national carbon-trading system in the coming days ... to encourage businesses to reduce greenhouse gases by using market incentives," said Ma.

He said China will step out phase-by-phase efforts to establish a national carbon market, but he didn't reveal when the overall trading market is likely to be operational.

Ma made the announcement at the One Planet Summit, which was hosted by French President Emmanuel Macron, World Bank President Jim Yong Kim, and UN Secretary-General Antonio Guterres.

More than 50 global leaders attended the one-day event that focused on concrete proposals and actions to fight climate change.

It was the first time China had talked about the specifics of setting up a national carbon trading system and national carbon market. So far, China has established local pilot carbon markets in some provinces and municipalities.

At Tuesday's gathering, Ma pledged that China will honor its commitments made two years ago, when up to 200 countries and economies signed the Paris Climate Change Agreement. Ma said China will transform through green and low-carbon development.

And he said the nation will also strengthen South-South cooperation in coping climate change.

But he urged rich nations to speed up their actions in capital and technology transfer to help poor countries with climate adaptation and mitigation.