US equity-index futures trimmed earlier gains following reports of an airstrike on Iran's South Pars gas field, a major energy asset. S&P 500 Index futures climbed 0.4% at 7:45 a.m. in New York, indicating cautious investor sentiment amid heightened geopolitical risk. The strike, claimed by Iranian state media, could disrupt global energy markets if production halts. South Pars, operated jointly with Qatar, supplies a significant portion of Iran's natural gas and is critical to its economy. Investors are monitoring potential oil price volatility as a key concern. CF Industries, Coupang, Duolingo, and Swarmer were among premarket movers, though specific details on their trading activity remain limited. Market watchers note the incident underscores the fragility of energy supply chains in volatile regions. The S&P 500 futures' modest gain reflects cautious optimism rather than robust buying pressure. Investors should watch for further developments in the Middle East, as any escalation could pressure risk assets broadly. The incident's full impact on energy prices remains uncertain at this early stage.