Canada and Denmark have reached a tentative agreement on where to set the boundary between the two countries in the Lincoln Sea.
The body of water is in the Arctic Ocean just north of Ellesmere Island and Greenland.
The tentative agreement builds on a 1973 treaty which established the maritime boundary between the two countries.
That treaty, however, did not include the Lincoln Sea because of technical differences over how the line should be determined.
Negotiators will now draft a treaty text for ratification by the two governments.
Once the treaty is ratified, Canada and Denmark will share a boundary more than 1,600 nautical miles long.
"Our government is pleased with the progress made on the Lincoln Sea boundary," Foreign Affairs Minister John Baird said in a statement.
He said the tentative agreement "lessens uncertainty and strengthens Canada's sovereignty over the Arctic."
Canada and Denmark continue to hold talks over ownership of Hans Island, an uninhabited two square kilometre rock in the Kennedy Channel midway between Ellesmere Island and Greenland.