US secretary of state John Kerry visited Chile to strengthen President Obama's commitment to the development of marine sanctuaries in the US and abroad, as part of an international forum at the coastal town of Vina del Mar.

Earlier on 5 October, at the second annual Our Ocean conference, the world's largest marine conservation park encompassing the remote Easter Island was announced. Kerry also told delegates that the US will create two new national marine sanctuaries at home to help tackle illegal fishing and environmental marine damage.

"As President Obama announced earlier, we are creating two new national marine sanctuaries in the US – one off the coast of Maryland and one in Wisconsin along the Great Lakes. But we also have plans in the works, which we are pursuing, for still another significant one in the Atlantic where we don't have the kind of presence that we want and should," said Kerry.

Amid warming ties between Cuba and the US, Kerry reported that he has held talks with President Raul Castro for the development of a protected marine sanctuary in Cuba's Caribbean waters.

"We are working to finalise now a new sister marine protected area arrangement with Cuba in order to protect its sites so we can collaborate on scientific research, education and sound management. We met in New York with President Castro, I met again with my counterpart, and we have agreed to meet again in Cuba in January or February when we will continue this march towards normalisation but, importantly, cooperation on the oceans as well," added Kerry.

The White House has said the US would launch a global initiative, called Sea Scout, to help in the fight against growing unregulated fishing and boost marine ecosystems. Kerry said the US was investing more than $500m (£330m) to promote the marine environment, including the purchase of state-of-the-art equipment to monitor and track the marine environment.

"We're investing more than half a billion dollars in a new US oceans observatory initiative. We're commissioning a system of moorings, gliders and autonomous underwater vehicles equipped with nearly 800 instruments to collect data such as ph, oxygen levels, transmission of carbon dioxide between the ocean and the atmosphere and concentration of phytoplankton," added Kerry.

Prince Alberto II of Monaco warned of the consequences if the international community does not act to protect the marine environment and reach an agreement at 2015's United Nations conference on climate change, COP-21.

"We are also aware of the other consequences that global warning has for our ocean, the destruction of fragile ecosystems, the migration of species and, above all, melting ice and the resulting rise in sea levels. These are all issues which have a profound impact on the balance and life of our ocean. They justify a relentless campaign to reach a binding agreement at COP-21," said Prince Albert.

The National Oceanic and Atmospheric Administration will announce steps as well to provide data and technical assistance to target illegal fishing, including a space-based monitoring sensor that will be implemented next year in Indonesia, the Philippines and three other countries.