Stock indices closed lower again last Friday. The S&P 500 fell by 0.61%, while the Nasdaq 100 plunged by 0.93%. The Dow Jones Industrial Average lost 0.26%.

Volatility remains high on Wall Street: futures on the indices have recovered slightly today, while oil prices have jumped to a more-than-three-year high amid the ongoing war in Iran. Bond gains have weakened as higher energy prices have intensified inflation concerns.

The S&P 500 gave back nearly a 1% advance after the United States intensified strikes on Iran to an unprecedented level. Both sides continued to escalate a conflict now in its second week, which pushed Brent crude above $100/bbl at the end of last week. All of this suggests that recent remarks from US President Donald Trump about an imminent end to the conflict are no longer calming markets. The Wall Street Journal, citing two US officials, reported that the Pentagon had sent an expeditionary Marine unit to the Middle East — a move that appears to escalate rather than de-escalate the situation.

On Friday, weak US growth data also hit sentiment, with Treasuries losing momentum and long?dated bonds performing worst. The dollar rose to its highest level since December. Data showed that job openings increased and layoffs fell, signaling demand for labor improved before the market showed signs of softening. The Fed's preferred inflation gauge, the core PCE index, matched expectations. The consumer sentiment index hit a three-month low.

Traders were also watching developments around a federal judge's subpoenas to the Federal Reserve Board from the Justice Department seeking documents on the central bank's headquarters renovation, as well as Jerome Powell's testimony to Congress on the matter.

As for the S&P 500 technical analysis, buyers' immediate task is to overcome the resistance level of $6,682. This would help the index gain renewed upside momentum and open the way to $6,697. Controlling $6,711 would further strengthen the bullish case. On the downside, buyers should defend around $6,672. A break below that level would quickly bring the trading instrument back down to $6,660 and could open the path to $6,651.