Canadian Prime Minister-designate Stephen Harper has rebuked the US ambassador last night for rejecting Canada's claims to the Arctic.
Mr Harper, whose Conservatives won a fragile mandate in Monday's election, said during the campaign that Liberal Prime Minister Paul Martin had needlessly exacerbated ties with the United States.
But Harper showed little hesitation in rebuking US envoy David Wilkins for making critical remarks about Conservative plans to boost Canada's presence in the far north.
"The United States defends its sovereignty, the Canadian government will defend our sovereignty," Mr Harper told reporters during his first news conference since the election.
"It is the Canadian people we get our mandate from, not the ambassador of the United States."
Mr Harper, vowing to boost defences in the Arctic to stop incursions by foreign vessels, plans to buy three new large icebreakers and build a deep-sea docking facility in the Arctic for a total cost of 2 billion Canadian dollars over 10 years.
The United States has long challenged Canada's claims to sovereignty over Arctic waterways - fabled as the Northwest Passage from the Atlantic to the Pacific - saying it considers much of the region to be international waters.
This could have serious implications if ice in the Northwest Passage starts to melt due to global warming and shipping companies decide to send vessels through the area to save time and fuel.