US stock futures fell Sunday evening, while crude oil prices surged, as investors weighed uncertainty over Iran and prepared for a pivotal inflation report later this week.

Futures linked to the S&P 500 (ES=F) slipped 0.4%, while contracts tied to the Nasdaq 100 (NQ=F) lost 0.6%. Dow futures (YM=F) declined 0.3%.

Energy markets climbed with instability driving oil higher. West Texas Intermediate (CL=F) crude jumped nearly 3% to trade near $78 a barrel, while Brent (BZ=F) crude climbed above $81 as traders assessed the risk of further disruption in the Middle East.

Market sentiment was rattled after President Donald Trump warned Iran of potential additional military action unless Tehran moved to rein in allied groups operating in Lebanon. The comments came as Vice President JD Vance opened a new round of diplomatic talks with Iranian representatives in Switzerland.

Attention now turns to Thursday’s release of the Personal Consumption Expenditures price index, the Fed’s preferred inflation gauge. Economists expect core PCE, which excludes food and energy costs, to show a modest acceleration from April levels.

The report arrives just days after the Fed struck a more hawkish tone, prompting traders to reassess the path of interest rates. Markets have increasingly pushed forward expectations for the next rate hike, making this week’s inflation data a critical test for investors looking for clues on whether price pressures remain stubborn enough to warrant additional tightening.