US Equity Indexes Fall as Trump's Warnings to Resolve Iran Standoff Send Treasury Yields Sharply Higher

05:00 PM EDT, 05/19/2026 (MT Newswires) -- US equity indexes slid as the 30-year Treasury yield rose to a two-decade high amid bets favoring higher interest rates and President Donald Trump's threat to Iran that strikes will resume if talks with the Gulf nations fail to produce a framework for a peace deal.

The Nasdaq Composite fell 0.8% to 25,870.71, with the S&P 500 down 0.7% to 7,353.61 and the Dow Jones Industrial Average lower by 0.7% to 49,363.88 at the close on Tuesday.

Materials, communication services, and consumer discretionary led the decliners. Health care and energy were the top gainers.

Most Treasury yields rose as investors looked for evidence of a rollback in Iran's nuclear ambitions in its ongoing talks with Gulf nations to agree on a framework for resuming peace negotiations with the US. The 30-year rate jumped 3.4 basis points to 5.18%, the strongest level since the global financial crisis, amid concern that a long, drawn-out war in Iran would further worsen inflation in the US. The 10-year climbed 4.2 basis points to 4.67%, the highest since January 2025.

President Trump warned strikes would resume against Iran as part of a push for a deal to end the war, Bloomberg reported. "I hope we don't have to do the war, but we may have to give them another big hit," Trump told reporters on Tuesday, following previous comments that Iran cannot have nuclear weapons.

Trump said Iran has "two or three days" to reach a deal to end the war or face renewed attacks, according to a report from Al Jazeera. An Iranian official said the US threat of a massive assault at any moment will be met "resolutely," and Iran is "prepared to confront any military aggression," the news report said.

Tehran's latest peace proposal to the United States involves ending hostilities on all fronts, including Lebanon, the exit of US forces from areas close to Iran, and reparations for destruction caused by the US-Israeli war, The Times of Israel cited Iran state media on Tuesday. The terms as described in the Iranian reports appeared little changed from Iran's previous offer, which Trump rejected last week.

In precious metals, gold futures fell 1.5% to $4,489.8, and silver futures dropped 4.2% to $74.19.

West Texas Intermediate crude oil futures fell 0.8% to $107.77, and Brent crude futures declined 0.8% to $111.24.

In economic news, Redbook US same-store sales rose by 8.1% from a year earlier in the week ended May 16 after a 9.6% year-over-year increase in the previous week.

"Coming off last-minute Mother's Day shopping on Sunday, sales and traffic slowed across the board in the middle of the week, but picked up during the weekend as graduation, BBQ season, and warm weather approached," Redbook noted.

US pending home sales increased more than expected last month as home buyers apparently shrugged off mounting economic uncertainty. The forward-looking indicator of home sales based on contract signings increased 1.4% month over month in April, the National Association of Realtors said. Analysts expected a 1% gain, according to a Bloomberg-compiled survey.

In company news, Alphabet's (GOOG, GOOGL) Google (GOOG) said Tuesday it introduced Gemini Spark, a 24/7 AI agent designed to handle and execute digital tasks and workflows, alongside other launches. The move comes amid a proliferation of AI models that is changing the tech landscape globally, including from Amazon.com (AMZN) -backed Anthropic.

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