Delegates at the April 15-17 Our Ocean Conference include 12 heads of state, around fifty ministers and officials, and representatives from 120 nations and entities, including the UN, EU and NATO.

"This is the biggest environment conference ever held (in Greece)," Environment and Energy Minister Theodoros Skylakakis told journalists.

He said that part of Athens' commitments are two new national parks -- one in the Ionian Sea for sea mammals and turtles, and another in the Aegean for seabirds, to be set into law by early next year.

"They will be among the largest in the Mediterranean," he said.

Greece has been repeatedly fined by the European Commission on environmental matters in the past decades.

In December, it was referred to the EU court of justice for failing to implement maritime spatial planning guidelines.

In a statement on Monday, nine environmental groups including WWF and Greenpeace hailed the new parks announcement as an "important initiative".

But they noted that the Ionian Sea park is to be created in an area already earmarked by Greece for hydrocarbon exploration.

"There can be no protected maritime area with hydrocarbon extraction," the groups said.

Skylakakis said the park under consideration is "much, much larger than any extraction area".

"Sea mammals will be afforded a very high level of protection," he promised.

Since the first Our Ocean conference in 2014, participating nations have committed more than $130 billion in ocean aid, Foreign Minister George Gerapetritis told reporters.

Greece will be placing particular emphasis this year on sustainable tourism, microplastics, eco-friendly shipping and the Mediterranean environment, he said.

"Each of us, especially those in coastal areas, swallows the equivalent of a plastic card each week (through microplastics in fish)," Gerapetritis said.

"And also through salt," added Skylakakis.

Observers say Our Ocean is the only conference to address all ocean-related issues under one roof.

At the previous summit in Panama in March 2023, participants pledged $19 billion in initiatives to protect oceans.

They included projects involving sustainable fishing, the fight against pollution, maritime security and protected areas.

"Other species cannot do much, they can merely adapt. Humans must react," Skylakakis said on Monday.

The European Union last year said it would dedicate 816.5 million euros ($884 million) to ocean-related projects.

Part of that was directed towards research to protect marine biodiversity and address the impacts of climate change on the seas, and a satellite to observe melting ice and monitor climate change effects.