The US has no fishing interests in the Ross Sea, but New Zealand companies take a large proportion of the annual Ross Sea toothfish catch - last year they landed 730 tonnes with an export value of $20 million.
The Herald understands the joint proposal was thwarted in Cabinet by ministers Gerry Brownlee, David Carter and Steven Joyce on the grounds it was not consistent with the Government's economic growth objectives.
There are tight regulations on fishing in the Antarctic, which is still treated as an exploratory fishery, including strict quota and reporting requirements on catch and bycatch.
However, Dr Earle said, there was no justification for fishing in the area and it was disappointing countries such as New Zealand were doing so.
"If you justify on the basis of food, there are plenty of other ways we can feed ourselves other than by taking 30-year old creatures from the deep sea that have never been on a menu before."
Countries had acted together to sign a treaty protecting the land of the Antarctic from commercial or military exploitation.
"But the waters have been treated very differently," she said. "Nations around the world have really just moved in with large fleets to take the toothfish, to take the krill. We are mining the ocean of the fish."
Foreign Minister Murray McCully said New Zealand would submit its own proposal for a protected area with the Commission for the Conservation of Antarctic Marine Living Resources, a 25-nation group which manages fishing and conservation in Antarctic waters.
He said it would still be the largest marine protected area anywhere in the world and would include an area in which fishing was banned.
But commercial fishing would still be allowed in other areas.
