Renewed Middle East fighting sent oil futures climbing and stocks tumbling Monday, with Brent crude jumping 1.8% to $93.10 a barrel after President Trump pledged to resume attacks on Iran. The escalation rattled investors already concerned about elevated energy prices and their impact on global markets.

The Dow Jones Industrial Average plunged 1.9%, or roughly 953 points, marking its worst performance since October. Tech stocks extended their recent volatility, with the Nasdaq dropping 2%, while the S&P 500 fell 1.6% to five-week lows, led by sharp losses in materials and industrial sectors.

Adding pressure, the consumer-price index rose 4.2% annually in May—a three-year peak driven by war-related energy costs. The data matched expectations and suggested the Federal Reserve may maintain current interest rates rather than cut them later this year, particularly following last week's strong jobs report that eased recession concerns.

The Strait of Hormuz disruption has created one of the largest energy shocks on record, weighing on market sentiment. Artificial-intelligence companies face particular scrutiny as investors reassess growth prospects amid persistent geopolitical uncertainty and elevated borrowing costs.