US-Canada Trade War Escalates With New Tariffs

Canadian and U.S. markets faced volatility on Monday, August 24, 2026, after the collapse of trade negotiations triggered a sharp escalation in tariffs, with Washington imposing new duties and Ottawa pledging retaliation. The breakdown in talks has placed billions in annual bilateral trade at risk and cast uncertainty over North American economic stability.

U.S. tariffs of 50 percent on approximately 20 billion dollars worth of Canadian goods took effect at 12:01 a.m. on Saturday, August 22. The measures cover a wide range of products, including steel, aluminum, dairy, lumber, and appliances. The action followed the failure of negotiations that concluded late on August 21. In response, Canadian Prime Minister Mark Carney announced retaliatory tariffs targeting U.S. steel, dairy, agricultural equipment, and electronics, scheduled to take effect on September 8.

The Toronto stock market experienced significant swings at Monday’s open. The S&P/TSX Composite Index briefly fell before recovering, with declines in industrial and consumer discretionary sectors offset by gains in materials. Analysts noted that while the direct market impact might be cushioned by strong commodity prices,...