01:14 PM EDT, 03/23/2026 (MT Newswires) -- US equity indexes jumped in midday trading Monday as President Donald Trump's move to postpone a planned attack on Iran's power infrastructure sent crude oil and government bond yields sharply lower.

The Nasdaq Composite advanced 1.3% to 21,927.8, with the S&P 500 up 1.2% to 6,586.6 and the Dow Jones Industrial Average climbed 1.5% to 46,252.2.

All sectors rose, with consumer discretionary, industrials, and materials leading the top gainers.

The drop came after US President Trump backed down from a weekend threat to "obliterate" Iran's power plants if Iran did not fully open the Strait of Hormuz to tanker traffic by the end of Monday. In a 6:00 am ET social media post Monday, Trump backed down from the threat, saying he would postpone any action for five days.

The US and Iran have had over the last two days "very good and productive conversations regarding a complete and total resolution of our hostilities in the Middle East," Trump said in a social media post. The constructive conversations will continue throughout the week, Trump added.

Over the weekend, Trump had warned that the US would "obliterate" Iran's power plants if Tehran did not fully reopen the crucial Strait of Hormuz within 48 hours. In response, Iran's military said it would attack regional energy infrastructure if the US decides to bomb its power plants, media outlets reported.

West Texas Intermediate crude oil futures sank 8.6% to $89.74.

US Treasury yields fell, with the 10-year down 2.6 basis points to 4.37% and the two-year retreated 3.4 basis points to 3.86%.

In economic news, US construction spending fell 0.3% in January, compared with a 0.1% increase expected in a Bloomberg-compiled survey, following an upwardly revised 0.8% increase in December.

The Chicago Federal Reserve Bank's monthly National Activity Index declined to minus 0.11 in February from 0.20 in January, below the 0.04 expected in a Bloomberg-compiled survey.

In company news, Insmed ( INSM ) said a phase 3b study of Arikayce as part of a multidrug regimen to treat patients with Mycobacterium avium complex lung infection who have not started antibiotics has met its primary and secondary endpoints. Shares jumped 5.6%, the biggest gainer on the Nasdaq.

Wells Fargo downgraded Thomson Reuters ( TMSOF ) to equalweight from overweight, while lowering its price target to $95 from $120. Shares of Thomson Reuters ( TMSOF ) slid 3.4%, the second-worst performer on the Nasdaq.

Cencora ( COR ) said it will acquire EyeSouth Partners' retina business for $1.1 billion as the drug distributor seeks to expand its network of retina specialists.

In precious metals, gold futures dropped 4.4% to $4,376.2 per troy ounce, and silver futures fell 1.3% to $68.78 per troy ounce.