updates at midafternoon

By Abigail Summerville, Twesha Dikshit and Joel Jose

June 24 (Reuters) - The Nasdaq and S&P 500 fell Wednesday afternoon as concerns about high-flying tech stock valuations persisted, erasing morning gains that came as oil prices retreated.

Oil prices fell to their lowest since the start of the Iran war as more oil tankers were expected to move out of the Strait of Hormuz. U.S. President Donald Trump said Iran had told Washington that no tolls were being sought.

Airlines and other travel stocks moved higher with the S&P 500 passenger airlines index .SPLRCALI last up nearly 4%.

Information technology stocks .SPLRCT fell 0.9%. Increased volatility in tech names has intensified focus on chipmaker Micron's MU.O results due after the bell. The stock has surged more than 250% in 2026 but was last down 3.2%.

Cerebras Systems CBRS.O tumbled 17.5% after the chip designer forecast full-year profit margins would drop below first-quarter figures in its debut report after going public. Also weighing on the stock, OpenAI announced on Wednesday its own in-house inference chip called Jalapeño.

Concerns around debt-backed spending by hyperscalers and a potentially more hawkish Federal Reserve have fueled the market downturn this week, wiping off more than $1 trillion in market value from the Nasdaq 100.

"The Middle East conversation is wrapping up ... energy prices are coming off," said Michael Monaghan, partner and portfolio manager at Founder ETFs. "But you continue to have the AI CapEx buildout where, for some reason, people like the recipients of the spend and have been punishing those doing the spending."

Six of the 11 major S&P 500 sectors moved higher, with the consumer discretionary sector .SPLRCD rising the most at 1.5%.

At 2:10 p.m. ET, the Dow Jones Industrial Average .DJI rose 161.43 points, or 0.31%, to 51,828.02, the S&P 500 .SPX lost 8.49 points, or 0.12%, to 7,356.97 and the Nasdaq Composite .IXIC lost 95.18 points, or 0.37%, to 25,491.85.

Homebuilders soared after Trump canceled a planned signing of bipartisan legislation aimed at speeding up availability of affordable housing. Hovnanian Enterprises HOV.N jumped 10%, while PulteGroup PHM.N and Toll Brothers TOL.N rose 7.5% and 6.4%, respectively.

Among other movers, Hertz HTZ.O tumbled 33% after the car-rental firm said it expects second-quarter adjusted core earnings near the lower end of its forecast range and announced a proposed offering of $100 million of common stock.

Traders are adding to bets of a second rate hike from the Fed by December-end, according to CME Group's FedWatch tool. Previously, the market expected a single 25-basis-point rise.

The closely watched Personal Consumption Expenditures Price Index, the Fed's preferred inflation gauge, could offer insight on the monetary policy path on Thursday.

Advancing issues and decliners were about even at a 1-to-1 ratio on both the NYSE and the Nasdaq.

The S&P 500 posted 22 new 52-week highs and four new lows while the Nasdaq Composite recorded 195 new highs and 135 new lows.