OTTAWA - The commander of North America's missile warning system is urging Canada and the U.S. to get on with upgrading the continent's defences in the face of threats unmatched since the Cold War.

Gen. Terrence O'Shaughnessy, the U.S. commander of the North American Aerospace Defence Command, or Norad, says Russia's recent military actions are one example of the risks facing Canada and the U.S.

Russia's actions include the resumption of fighter-jet patrols in the Arctic after 30 years, regular flights to the edge of Canadian and American airspace by heavy bombers and deploying cruise missiles in the North.

Canada and the U.S. are looking to upgrade the continent's defences, including the 1980s-era chain of radars in Canada's Arctic that supports Norad, to address these and other threats.

But O'Shaughnessy warns that the two countries can't fall into what he called "the paralysis of analysis trap" by endlessly discussing the problem and not acting.

O'Shaughnessy says Canada and the U.S. also need to better defend shared infrastructure such as power grids and find ways to make it too dangerous for anyone to contemplate an attack on North America.