US equity indexes closed little changed on Monday, with the S&P 500 slipping 0.19% and the Nasdaq Composite nearly flat, as a fragile recovery in semiconductor shares was offset by renewed volatility in energy markets. The Dow Jones Industrial Average fell 0.59%, while Brent crude oscillated around $89 a barrel after briefly topping $90 for the first time since early June. The mixed session reflected a market caught between diplomatic overtures in the Middle East and a sharp escalation of threats to regional energy infrastructure.

The day’s swings were driven by conflicting signals from the Gulf. Iran’s foreign minister, Esmaeil Baghaei, signalled that mediators had kept diplomatic channels active and had proposed a ten-day ceasefire, a development that briefly pushed oil prices lower and lifted risk appetite. But the relief proved short-lived. Yemen’s Iran-aligned Houthis declared a naval blockade on Saudi Arabian ports, threatening the Red Sea export route that allows the kingdom to bypass the Strait of Hormuz. Viewed from Washington, President Donald Trump later hardened his rhetoric, vowing retaliation for the deaths of US soldiers, which traders in New York said kept a floor under crude and limited equity gains.

Against this backdrop, the technology sector found its footing. The Philadelphia Semiconductor Index rose 0.6%, clawing back a fraction of last week’s rout that had pushed it more than 20% below its late-June record and into a bear market. Memory-chip makers including Micron Technology and Western Digital led the advance, while Alphabet gained 1.5% on a report that Google is developing a server chip integrated with its Gemini AI model. The rebound, however, lacked conviction: trading volumes on US exchanges were about 22% below the twenty-day average, and declining issues outnumbered advancers on both the NYSE and Nasdaq by a ratio of roughly 1.7 to 1.

European markets reflected similar cross-currents. The Stoxx 600 edged down 0.3%, with energy shares rising 0.86% while travel and leisure stocks fell. In London, the FTSE 100 dropped 0.71% as UK gilt yields climbed to their highest since late May after new Prime Minister Andy Burnham unnerved investors by pledging to seek “any flexibility” within fiscal rules, and his finance minister Rachel Reeves resigned. Bitcoin held above $64,000, supported by a second consecutive week of net inflows into spot ETFs, though analysts in Latin America noted that elevated Treasury yields and oil-driven inflation concerns capped further upside.

The next factual milestone is the start of megacap earnings season on Wednesday, when Alphabet and Tesla report second-quarter results. With S&P 500 profit growth expected to reach 26% year-on-year, according to LSEG data, investors will scrutinise whether AI-related capital spending is translating into revenue, and whether the chip sector’s recent sell-off was a correction or the start of a deeper reassessment.