Foreign Affairs Minister Lawrence Cannon expressed "regret" on Wednesday after France renewed an old claim to Atlantic seabed rights off the Saint-Pierre and Miquelon shores.
The move could cool off the unusually warm relations that have developed between the two countries in recent months.
On Wednesday, France submitted a letter of intent to the United Nations Commission on the Limits of the Continental Shelf claiming an extended continental shelf extending from the islands.
The isolated islands have belonged to France since 1763. They lie roughly 25 kilometres south of Newfoundland and Labrador and are home to roughly 6,000 inhabitants.
The residents of the islands, mostly fishermen, are seeking the right to tap into the same offshore oil reserves that have led to Newfoundland's recent prosperity, as well as marine life resources.
In a statement, Cannon said the "maritime delimitation" between Canada and France was decided on June 10, 1992, by a tribunal, and he had no intention of revisiting the issue.
The tribunal was established in 1989, after France and Canada agreed to let arbitration decide the dispute.
"Canada does not recognize France's claim to any area of the continental shelf in the northwest Atlantic Ocean beyond the area set out in the arbitration decision, and Canada has made France aware of its position on several occasions, and again recently," Cannon said in the tersely worded statement.
"Canada will take all necessary measures to defend and protect its rights with respect to its continental shelf."
France had sought a 48,000 square kilometre exclusive economic zone around the islands in 1989, but was only awarded a quarter of that by the tribunal.
Canada's Exclusive Economic Zone completely surrounds the islands as well as the Ocean area residents claim should belong to them.
