The Government has signed up to a global oceans partnership at a UN sustainable development summit in Rio de Janeiro.
The Rio+20 conference which opened on Wednesday is being held in 20 years on from the original Earth Summit in Brazil.
In her address, Environment Minister Amy Adams told the summit that New Zealand is particularly concerned about harmful fisheries subsidies which are depleting global fish stocks.
She said ensuring small island developing states get a greater share of their marine resources is a priority.
The oceans agreement signed up to by New Zealand is aimed at better management of fisheries, protecting marine environments and addressing pollution.
Nine other countries are in the partnership, including Australia, South Korea and Norway, and 63 organisations including fishing and seafood companies.
United Nations secretary-general Ban Ki-moon warned at the opening of the summit that progress on sustainable development was too slow and that words must translate into action.
The Green Party says New Zealand has failed to meet promises made at the Earth Summit.
Ms Adams says that while she would have liked to see some things come to fruition, the summit is getting all countries to move forward.
She told Morning Report the conference brings together hundreds of countries with considerably different economic and political frameworks.
"I think we have to work on the basis of taking the progress we can and supporting them to continue to work in that direction."
NZ teenager addresses summit
The opening session also heard from Wellington schoolgirl Brittany Trilford, who won a competition organised by climate change campaign group tcktcktck to send a message behalf of the world's youth.
The 17-year-old told world leaders they shouldn't just participate in a talk fest.
Referring to the remaining length of the summit, she said: "You have 72 hours to decide the fate of your children - my children - my childrens' children - and I start the clock now.
"Are you here to save face - or are you here to save us?"
The teenager said promises are often left empty and the leaders need to commit to them and continue working to fulfill them when they return home.
Twenty years ago the historic Earth Summit was held in the Rio and gave rise to UN conventions on climate change, biodiversity and desertification, as well as the Agenda 21 blueprint for sustainable development.
Rio+20 brings together 191 UN members, including 86 presidents and heads of government.