Canadian PM Mark Carney says deal on ‘over the horizon’ radar is part of effort to assert Canada’s sovereignty over Arctic as US priorities shift

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The Canadian prime minister, Mark Carney, has announced a C$6bn deal (A$6.6bn) with Australia to develop an Arctic radar system, warning that Canada must take more responsibility for its defence as US priorities shift.

Carney made the announcement on Tuesday in Iqaluit, capital of the Nunavut territory in the Canadian Arctic, on the final leg of his first official trip as prime minister since taking over from Justin Trudeau last week.

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