The U.S. stock market closed lower on Thursday, with the S&P 500, Nasdaq Composite, and Dow Jones all posting modest declines. The S&P 500 fell 28.01 points (-0.38%) to 7,337.11, the Nasdaq Composite dropped 32.75 points (-0.13%) to 25,806.19, and the Dow Jones declined 313.62 points (-0.63%) to 49,596.97. The moves were relatively broad, with all three major indices ending the session in the red. The tone of the session was mixed, with a risk-off sentiment prevailing as investors awaited updates on the potential Iran-US deal. Crude oil prices remained steady, with U.S. oil falling below $100 a barrel, which contributed to the cautious market sentiment.

The market's performance was influenced by several macro and sector drivers. Investors were closely monitoring developments in the Iran-US negotiations, with hopes that a deal could be reached to alleviate tensions in the Middle East. This optimism led to a slight retreat in oil prices, which in turn impacted energy-related stocks. Additionally, the market was affected by a broader risk-off sentiment, with investors pulling money out of equities and into safer assets. The S&P 500 had previously hit fresh records before retreating, indicating a potential exhaustion of the recent rally. The Russell 2000 also scored record closes, suggesting that the market's strength was not limited to large-cap stocks. However, the overall tone of the session was one of caution, with the market looking for direction amid the uncertainty surrounding the Iran-US deal and the broader geopolitical landscape.