President Donald Trump has vowed to impose additional tariffs on Canada, citing the country's failure to contain wildfire smoke that has spread across large parts of the United States.
The announcement marks a significant escalation in trade rhetoric, linking environmental externalities directly to commercial policy.
The threat introduces a new variable into U.S.-Canada trade relations, which have already been strained by broader tariff measures implemented at the start of Trump's second term.
By framing wildfire smoke as a cost that should be borne by Canadian exporters, the administration is signaling a willingness to expand the scope of trade remedies beyond traditional economic metrics.
Markets are likely to monitor the situation for any concrete policy proposals or legislative action.
The move adds to the uncertainty surrounding North American supply chains, which have been navigating a complex landscape of tariffs and trade barriers.