(Updates with index/price moves, macroeconomic data and company/geopolitical news from the first paragraph.)
US equity indexes declined as Iran-backed Houthi attacks on Saudi Arabian energy facilities sent crude oil higher, fueling inflation concerns.
The Dow Jones Industrial Average dropped 1.2% to 52,786.07, the Nasdaq Composite declined 0.3% to 26,421.41, and the S&P 500 retreated 0.6% to 7,673.52 on Tuesday. Energy and utilities were among the gainers. Healthcare and financials led decliners.
Iran's Fars news agency reported an explosion in the southern Jask area of the Islamic Republic, after reports of earlier explosions heard on the country's Kharg Island, Al Jazeera, a Middle Eastern broadcaster, reported.
This comes as Yemen's Tehran-backed Houthis attacked energy facilities and cities in US ally Saudi Arabia on Tuesday, wounding more than 70 people and underscoring the risk of the Iran conflict escalating into a wider regional war, Reuters reported.
Saudi Arabia said the attacks stopped operations at several energy facilities in the kingdom's south, Bloomberg reported, while noting a pick-up in buying by China, the world's largest importer. The US struck three Iranian tankers on Saturday in response to attacks on two US Navy warships.
"As we ponder a prolonged conflict, our expectations increasingly shift to a slower recovery in Middle East oil supply," Peter Taylor, head of commodity strategy at Macquarie, said in a note. "In this environment, we would anticipate deficits persisting through [year-end 2026], with the market approximately balanced in 2027."
The front-month US West Texas Intermediate crude oil contract jumped 2.8% to $94.05 per barrel, and global benchmark North Sea Brent advanced 2.2% to $99.11 per barrel.
Most US Treasury yields rose, with the two-year up 1.7 basis points to 4.40%, amid concern that higher crude oil prices undermine the Federal Reserve's efforts to bring inflation back to its 2% target. The 10-year yield was steady at 4.79%.
Gold futures dropped 1.7% to $4,403.4.
In company news, Novartis (NVS) sank nearly 14% after the company said its phase 3 Harbor study evaluating delpacibart etedesiran in patients with myotonic dystrophy type 1 failed to meet its primary endpoint of video hand opening time. Amgen's (AMGN) experimental heart drug olpasiran may still show a meaningful reduction in major cardiovascular events, even after Novartis' competing drug failed in a large study, UBS Securities said in a note. Amgen shares slumped 10%, the worst performer on the S&P 500, the Nasdaq, and the Dow.
Intel (INTC) is expected to raise personal computer central processing unit prices by another 10% in early October, Digitimes reported, citing supply chain sources. Intel shares jumped 9.1%, among the top gainers on the S&P 500 and the Nasdaq.
Palantir Technologies (PLTR) and Nebius Group (NBIS) agreed on a strategic partnership that will give Palantir commercial customers access to Nebius' artificial intelligence-native compute infrastructure and cloud platform, the companies said Tuesday. Nebius shares surged 7.7%, among the biggest Nasdaq outperformers.
In economic news, the National Federation of Independent Business' monthly sentiment index fell to 98.7 in August from 99.8 in July, with declines in six of the 10 components, particularly the economic outlook.
"Uncertainty remains elevated among small business owners as they face a mixed set of challenges with weakened sales, supply chain disruptions, and inflation pressures," said NFIB Chief Economist Bill Dunkelberg. "While expectations for the overall economy dimmed, Main Street owners remain largely positive about the health of their own businesses."