At a meeting in June 2022, all of the WTO's 164 members agreed to reduce the fisheries subsidies that spur over-fishing.

China is a major subsidiser, so its endorsement for the deal would be important, observers say.

On Friday, Switzerland also said it would ratify the deal during a meeting at the annual World Economic Forum in Davos.

While landlocked Switzerland is not a significant fishing nation, activists said it was still important since the new rules only come into effect when they are ratified by some 100 WTO members. Isabel Jarret from NGO The Pew Charitable Trusts called it an "absolutely critical step".

(Reporting by Twinnie Siu in Hong Kong and Emma Farge in Geneva; Editing by David Goodman and Sharon Singleton)