No fishing in the Arctic

The Arctic nations - Canada, the United States, Russia, Greenland (Denmark), and Norway - have signed an accord just this last week not to fish in the open waters of the central Arctic Ocean.
This might not seem like much of a big deal, and it might still be of little practical value unless other major fishing powers, like China, Japan, South Korea and the counties of the EU, can also be persuaded to sign on.
But, given that these Arctic nations are not exactly best buddies in certain other political spheres, and given the potential economic value of fishing in the newly accessible waters around the North Pole, it is actually a remarkable example of international cooperation on a thorny environmental/economic issue.
So, if they can agree on this, why can't they manage to resolve decades of argument over the national boundaries in the area? Or, even better in my view, agree to make the whole region, outside 200km of the coastlines, international waters, owned and preserved jointly as a part of our shared human patrimony, much like Antarctica.
And, if we can agree to disallow fishing there, can we not agree not to extract any minerals - oil, gas, metals, etc - the root source of most of the current acrimony in the region?