More than 100 countries will meet in Nairobi next week to discuss a treaty aimed at tackling plastic pollution, with some calling for production caps as well as commitments to phase out more single-use plastic products.

China has introduced punishments and other legal constraints aimed at curbing plastic pollution, Ministry of Ecology and Environment spokesman Liu Youbin told reporters. China would actively participate in international pollution control efforts, he added.

China, which produces about 60 million tonnes of plastics annually, published a "five-year plan" on plastic pollution last September, calling for the creation of a "control mechanism" covering the entire production and consumption chain by 2025.

It is phasing out single-use products in major cities, including straws and bags, as well as the thin plastic film used on farms to retain crop moisture.

After banning the import of foreign plastic trash, China played a "constructive role" in 2019 to amend the Basel Convention on hazardous waste to include plastics, said Patrick Yeung, Ocean and Plastic Programme Lead with the Worldwide Fund for Nature (WWF) in China.

"We hope to see more of such moves from China if it wishes to continue to be seen as demonstrating leadership in pushing for global environmental progress," he said.

More than 50 countries are calling for the new pact to set a plastic production cap, but China's position remains unclear. The environment ministry declined to comment.

Wang Wang, chairman of the China Scrap Plastic Association, told Reuters that "restricting plastic production is a non-industry viewpoint and won't solve the real problem", which requires the "responsible use of plastic".

(Reporting by Min Zhang and David Stanway; Editing by Shivani Singh)

By Min Zhang and David Stanway