OTTAWA, CANADA - Prime Minister Stephen Harper flew a military helicopter around an iceberg, sailed a warship, and dove in a navy submarine Wednesday to herald Canada's claim to the resource-rich Arctic.

On day three of a five-day visit to the far north, Harper was taking part in an annual military exercise trumpeting Canada's sovereignty over a large Arctic tract east of Baffin Island, where Russian and US submarines are said to prowl.

Tuesday, Harper also held a cabinet meeting in Iqaluit, Nunavut and dined on seal in support of Canada's maligned seal trade.

"We must never forget that just as the eyes of southern Canadians gaze northward, so too do those beyond our borders," Harper told sailors in a speech Wednesday on the deck of HMCS Toronto as it sailed through Frobisher Bay.

"With other countries probing our north by sea and in the air, the work you are doing here to protect our sovereignty has never been more important," he said.

"Protecting national sovereignty, the integrity of our borders, is the first and foremost responsibility of a national government."

Later, Harper zipped across Frobisher Bay to the submarine HMCS Corner Brook and took its reigns as it slipped beneath the icy waters for a 30-minute trip.

His office said he also took control of a large Sea King helicopter as it flew past an iceberg, and briefly steered the warship HMCS Toronto.