U.S. stocks fell and Treasury yields hit multiyear highs after Yemeni rebels attacked Saudi Arabian energy facilities, pushing oil prices to their highest levels of the summer. The attack, which disrupted operations at key Saudi sites, raised concerns about global supply stability. Meanwhile, copper prices reached fresh records on both U.S. and UK exchanges, driven by trade flow distortions and supply challenges at major mines worldwide.

In other economic news, the U.K. sold 4.25 billion pounds ($5.75 billion) in long-dated debt at the highest yield since 1998, reflecting rising borrowing costs for governments. The European Central Bank is expected to raise its key interest rate to 2.5% from 2.25% on Thursday, as eurozone inflation hit a nearly three-year high in August. U.S. small business confidence dipped in August, while the Employment Trends Index rose to 108.53 from a revised 107.76 in July.

On the geopolitical front, a second wave of attacks by Iranian-backed forces on U.S. Navy ships missed their targets but highlighted Tehran's increasingly sophisticated missile capabilities. Treasury Secretary Scott Bessent's support for the yen has created potential problems for stocks. German exports declined for the first time in six months, though exports to the U.S. jumped nearly 20% month-over-month. China's trade surplus widened as export growth accelerated, supporting its economy amid weak domestic consumption.

Finally, a new OECD report shows a significant drop in reading scores for 15-year-olds across 91 countries and economies compared to a decade earlier, raising concerns about global education trends.