The committee is trying to ensure the Cook Islands retains ownership of the seabed resource and that it is protected by robust legislation.
It would also develop policy to govern any development, and ensure it is done in the most environmentally sustainable way. All but two of the 50 members of the Koutu Nui backed the committee.
The deputy prime minister, Sir Terepai Maoate, who initiated the establishment of the committee last year, welcomed the Koutu Nui support.
He said it is important that the traditional leaders are kept aware of the work of the committee and the cautious steps being taken in possible development of the nodules.
