A global agreement designed to protect the world's oceans and reverse damage to marine life is set to become international law.

The High Seas Treaty received its 60th ratification by Morocco on Friday, meaning that it will now take effect from January.

The deal, which has been two decades in the making, will pave the way for international waters to be placed into marine protected areas.

Environmentalists heralded the milestone as a monumental achievement and evidence that countries can work together for environmental protection.

Covering more than two-thirds of the ocean, the agreement sets binding rules to conserve and sustainably use marine biodiversity, United Nations Secretary-General Antonio Guterres said.

Decades of overfishing, pollution from shipping and warming oceans from climate change have damaged life below the surface. In the latest assessment of marine species, nearly 10% were found to be at risk of extinction, according to the International Union for Conservation of Nature (IUCN).

Three years ago countries agreed that 30% of the world's national and international waters - high seas - must be protected by 2030 to help depleted marine life recover.

But protecting the high seas is challenging. No one country controls these waters and all nations have a right to ship and fish there. Currently just 1% of the high seas are protected, leaving marine life at risk from overexploitation.

So, in 2023 countries signed the High Seas Treaty pledging to put 30% of these waters into Marine Protected Areas.

With many nations requiring parliament approval, ratification can often take more than five years. Elizabeth Wilson, senior director for environmental policy at the Pews Charitable Trust, noted this was record time for ratification.

Kirsten Schuijt, director general of WWF International, hailed the treaty as a significant milestone for ocean conservation, emphasizing collaboration across international waters.

The treaty's framework will enable countries to propose marine protected areas, which will be voted on by signatory nations, although some critics express concern over the process of environmental impact assessments conducted by individual countries.

As the largest ecosystem, the ocean plays a vital role for life on Earth, contributing an estimated $2.5 trillion to global economies and providing significant oxygen for terrestrial organisms.