Canadian Stocks Slide as U.S.-Iran Deal Stalls

Canadian equities fell on May 27, 2026, as progress on a U.S.-Iran nuclear agreement stalled, damping risk appetite. The S&P/TSX Composite Index declined, with energy producers leading losses amid the geopolitical uncertainty. The long-anticipated deal, aimed at lifting sanctions and easing Middle East tensions, hit a fresh snag in talks overnight. Traders reacted by shedding positions in oil-sensitive and financial stocks, pushing the broader market into negative territory. Materials shares also retreated. The Canadian dollar traded weaker against the U.S. dollar as the cautious mood spread. The breakdown in negotiations removed a key pillar of support for a recent risk-on rally.