U.S. President has complained in the past about Canadian dairy controls and softwood lumber

U.S. President Donald Trump is complaining about Canadian trade practices while threatening some as-yet-undefined international tax that has revived fears he might be contemplating new American import penalties.

He made the remarks at the White House on Monday while unveiling a long-awaited infrastructure plan. During a lengthy session with reporters, he complained about countries considered allies of the U.S.

"Canada does not treat us right in terms of the farming and the crossing the borders," Trump said.

"We cannot continue to be taken advantage of by other countries."

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