Speaking before a room full of policymakers from midwestern Canada and the United States, former prime minister Stephen Harper said the ongoing trade war with the U.S. is a "wake-up call" for Canada to diversify its trade and export markets.

Stephen Harper calls himself the most pro-American prime minister in Canadian history. But the advice he gave recently to Mark Carney’s government was to take a different path — and reduce the country’s close integration with the US.

Rather than continuing to retaliate with tariffs of its own, the Canadian government has begun to confess that such a tactic may be a losing battle against Donald Trump.

President Donald Trump published a letter to Prime Minister Mark Carney on Thursday, accusing Canada of having "financially retaliated" against the U.S.