U.S. and New Zealand officials say they've reached agreement on a proposal to establish the world's largest marine protected area in the Antarctic's Ross Sea.

The two countries tentatively agreed on the joint proposal at the 31st meeting of the Commission for the Conservation of Antarctic Marine Living Resources in Hobart, Australia, a U.S. State Department release reported Thursday.

The Ross Sea is of tremendous conservation and scientific value and is a focal point for U.S. marine conservation efforts in Antarctica, the release said.

The joint plan was not finalized during the meeting, U.S. officials said, because opposition from a small number of members prevented the commission from reaching the consensus required to approve the Ross Sea proposals.

It was agreed, however, to convene a special meeting in Germany in July 2013 to consider and make decisions on the pending marine protected areas, officials said.