03:59 PM EDT, 03/26/2026 (MT Newswires) -- US equity indexes slumped ahead of Thursday's close as President Donald Trump cast doubt over reaching a diplomatic solution with Iran, putting the onus on Tehran to find an off-ramp from the war.

The Nasdaq Composite dropped 2.3% to 21,423.2, with the S&P 500 down 1.6% to 6,486.5, and the Dow Jones Industrial Average 1% lower at 45,942.7 in the final leg of trading.

A US proposal to end almost four weeks of fighting is "one-sided and unfair", Reuters reported Thursday, citing a senior Iranian official. The official said the proposal, conveyed to Tehran by Pakistan, "was reviewed in detail on Wednesday night by senior Iranian officials and the representative of Iran's Supreme Leader".

Meanwhile, Trump said it's up to Iranian leaders to convince him to end the Middle East conflict, CNN reported Thursday. Trump pointed out he isn't sure if the US can reach a diplomatic agreement with Iran, adding that Washington has additional targets "to hit before we leave."

This comes as the commander of the Islamic Revolutionary Guard Corps Navy in Iran, a key figure behind the near-total blockade of the Strait of Hormuz, has been killed, CNN cited Israeli Defense Minister Israel Katz as saying.

West Texas Intermediate crude oil futures jumped 4.4% to $94.31 intraday.

Most US Treasury yields advanced, with the 10-year up 9.2 basis points to 4.42% and the two-year higher by 11.5 basis points to 3.99%, reflecting concern that an extended Iran war would fuel inflationary pressures.