Global leaders representing UN member states, private sector companies and civil society have affirmed the urgent need to invest in ocean protection and restoration, the World Wide Fund For Nature (WWF) said on Friday.

In a statement after the conclusion of the five-day UN Ocean Conference in the Portuguese capital Lisbon, the WWF called on leaders to "seize the momentum" and resolve long-standing issues surrounding protection of the high seas, plastic pollution and harmful fisheries subsidies by ratifying global treaties.

"The conference underscored the severity of the multiple threats facing the world’s ocean, including overfishing, plastic pollution and climate change," it said.

Citing latest figures by the UN's Food and Agriculture Organization (FAO), it said 35.4% of fish populations are overfished, up from 10% in the 1970s.

"Restoring ocean health requires urgent action at all levels, from all sectors – local to global ... the ocean, climate and coastal communities worldwide need real progress, not promises, when it comes to ocean health," said WWF head Marco Lambertini.

Pepe Clarke, oceans practice lead at WWF International, called for new treaties for the high seas and plastics and continued action to curb harmful fisheries subsidies.

“Local solutions must also receive investment in order to scale up and have lasting benefits for communities," he said. "This means expanding the rights of small-scale fishers to manage the resources on which they depend, and other sustainable development pathways."/aa