Countries that have reached an agreement to protect whales and dolphins will meet in Auckland on Tuesday and Wednesday in the hope of adding Tonga and Britain to its list of signatories.
The Pacific Cetaceans Memorandum of Understanding was negotiated between 2003 and 2006, and signed in Samoa two years ago to help protect species such as humpback and blue whales.
Signatories to the agreement, which is not legally binding, include New Zealand, Australia, Niue and France.
The Department of Conservation's senior international relations officer, Mike Donoghue, says the meeting will focus on prioritising the most urgent action needed.
Mr Donoghue says that without the memorandum, smaller nations would be trying their best with limited resources.