02:31 PM EDT, 05/18/2026 (MT Newswires) -- US benchmark equity indexes were mixed after midday Monday as oil prices rose amid new developments in the Middle East conflict, while traders braced for Nvidia's ( NVDA ) latest financial results due out later in the week.

The Nasdaq Composite was down 0.7% at 26,049.9 intraday, while the S&P 500 shed 0.3% to 7,387.2. The Dow Jones Industrial Average was 0.1% higher at 49,571.2. Most sectors were in the green, led by energy, while technology saw the steepest decline.

West Texas Intermediate crude was up 1.5% at $107.01 per barrel, while Brent rose 1.4% to $110.84.

Iran has provided an updated proposal for a deal to end the war with the US, though the White House indicated it doesn't reflect a meaningful improvement from a previous offer and is insufficient, Axios reported Monday, citing a senior US official and a source briefed on the matter.

The Strait of Hormuz -- the world's most important chokepoint for crude flows -- remains largely shut as tensions between the US and Iran continue, with no end in sight. Over the weekend, US President Donald Trump said the "clock is ticking" for Iran to strike a deal.

US Treasury yields were mixed intraday Monday, with the 10-year rate up 1.2 basis points at 4.61% and the two-year rate little changed at 4.08%.

Nvidia ( NVDA ) shares were down 1.8%, the second-worst performer on the Dow. The chipmaking giant -- which is scheduled to release its latest quarterly results after the markets close Wednesday -- is considered by many investors as the "scoreboard" for the artificial intelligence boom, Saxo Bank said in a note Monday.

"The company does not only need to show that demand remains strong. It may need to show that demand is still accelerating, margins remain resilient, competition risk is contained, supply constraints are manageable, and China risk is manageable," Saxo said. "That is a high bar. And when the bar is high, even good news can create volatility."

Retail giants Walmart ( WMT ) , Home Depot ( HD ) , TJX (TJX), Lowe's (LOW) and Target ( TGT ) are also expected to report this week.

Home Depot ( HD ) and Lowe's are likely to lower their full-year guidance as the home improvement retailers face pressure from weak consumer sentiment, Oppenheimer said in a note.

NextEra Energy ( NEE/PW ) and Dominion Energy ( D ) agreed to merge in all-stock deal to create the largest regulated electric utility in the world. Dominion shares were up 8.6% intraday Monday, the second-biggest gainer on the S&P 500, while NextEra fell 6.6%.

In economic news, US homebuilder confidence unexpectedly rose this month despite elevated mortgage rates, macro uncertainty and continued affordability challenges, data from the National Association of Home Builders and Wells Fargo showed.

"Soft homebuilder sentiment is consistent with our view that housing starts will mostly move sideways for the next couple of quarters before starting to edge up slightly around year-end, when we expect mortgage rates to be lower as the (Federal Reserve) implements the first of two rate cuts we expect," Oxford Economics said in a note.

Gold was down 0.2% at $4,553.40 per troy ounce, while silver fell 0.2% to $77.41 per ounce.