Manado, Indonesia - The leaders of six South-East Asian nations adjoining the region's so-called Coral Triangle agreed Friday to implement comprehensive measures to protect the world's most diverse marine region.

At the World Ocean Conference in Manado, Indonesia, the leaders of the Philippines, Malaysia, Indonesia, Papua New Guinea, East Timor and the Solomon Islands passed an action plan declaring one fifth of the coastal waters a protected zone.

Twenty per cent of the 5.4-million-square-kilometre territory, which is home to coral reefs, mangrove woods and sea grass, will be off-limits to fishing fleets.

"The Coral Triangle is a globally recognized treasure," Indonesian President Susilo Bambang Yudhoyono said. "It is the global centre of marine life abundance and marine life diversity. If its natural systems were to be damaged beyond repair, it would be a tragedy for the whole planet."

The leaders pledged 13 million dollars for protective measures, while the US pledged 40 million dollars and Australia 55 million dollars, bringing the total of funds for the Coral Triangle, along with other pledges, to more than 300 million dollars, David McCauley, a climate expert of the Asian Development Bank, said.

The Coral Triangle is home to one third of the world's coral reefs, more than 75 per cent of coral species as well as thousands of fish species. About 120 million people live around its edges.

The triangle is threatened by pollution, destructive fishing methods using explosives or poison, overfishing as well as climate change.

Rising water temperatures endanger the corals, what are used as breeding grounds for countless fish species.

Environmental pressure groups World Wide Fund for Nature (WWF), Conservation International and The Nature Conservancy welcomed the governments' action plan.

Healthy reef systems help buffer coastal communities from severe storms and tsunamis," the said. "Protection of reefs and mangroves in the Coral Triangle will be vital to help people adapt to increasing storm severity, an effect of climate change."

The six nations joined 70 other participating states in the conference Thursday, passing the so-called Manado Declaration, where they demand that the protection of oceans and costal regions be discussed at the upcoming negotiations for a new world climate treaty in December.

"WWF urges world leaders meeting at the UN Climate Conference in Copenhagen later this year to support Coral Triangle countries in their efforts to protect their most vulnerable communities from the impacts of climate change and the loss of food and livelihoods," said WWF Director-General James P Leape.(dpa)