Ocean conservationists called on Friday for countries to speed up ratification of a treaty to protect the high seas, a year after the historic text was approved by UN member states.

The treaty -- which took 15 years to be approved -- aims to protect marine ecosystems that are vital to humanity but under threat by pollution.

Members of the United Nations finalized it in March last year, before formally adopting it in June.

Since then, it has been signed by 85 states -- but ratified by only two, Palau and Chile. It needs to be ratified by 60 before it can go into effect.

"Other countries have started their ratification processes but are moving too slowly," said Greenpeace campaigner Laura Meller in a statement.

"Many governments want to present themselves as ocean champions -- we expect them to follow in Chile and Palau's footsteps and bring the treaty to life, so that the real work to protect the oceans can start."

Non-governmental organizations still hope 60 countries can ratify the treaty by 2025.

"We welcome the progress made in the global Race for Ratification of the High Seas Treaty over the past year," said Rebecca Hubbard, director of the NGO coalition High Seas Alliance.

The treaty has given "hope to citizens around the world that leaders will act. Yet time is not on our side," she added. (AFP)