Trump had given out his personal cell phone to numerous world leaders after taking office including Trudeau as well as the leaders of France and Mexico.
When Trump imposed tariffs on Canadian lumber on April 25, 2017, Trudeau called him to speak of the decision.
Canadian officials released a press readout of the phone call, which is how U.S. government officials found out the call took place, the Washington Post recently reported.
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Trudeau told his American counterpart that “Canada will vigorously defend the interests of the Canadian softwood lumber industry,” according to the release from his office.
The readout also detailed other pieces of the conversation, including a discussion of the ongoing dairy dispute.
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U.S. officials were reportedly left scrambling to create a short public readout of the call.
“We had no idea what happened,” a senior U.S. official said.
After the conversation, it was explained to Trump that by law, he needed to follow protocol going forward and take all calls through official channels.