U.S. stock index futures showed mixed performance on Monday, with rising oil prices driven by the latest Middle East developments fueling concerns over regional instability.

Futures for the blue-chip index declined by 0.3%, while S&P 500 futures fell 0.1%. In contrast, Nasdaq 100 futures advanced 0.1%. Conflicting reports regarding an alleged Iranian attack on a U.S. naval vessel contributed to a rebound in futures from earlier lows. Iranian media claimed a ship was expelled from the Strait of Hormuz.

Iran's state television reported that the Iranian navy prevented a "U.S.-Zionist" warship from entering certain waters. Separately, Iran's Fars News Agency stated that a U.S. warship near Jask Island was hit by two missiles after ignoring warnings. Neither report has been independently verified.

The U.S. Central Command later posted on social media platform X: "No U.S. naval vessel was struck."

Oil prices climbed across the board on Monday. U.S. West Texas Intermediate crude futures rose 3%, surpassing $105 per barrel, while the international benchmark Brent crude also increased 3%, exceeding $111 per barrel. Energy prices retreated from morning highs following reports questioning Iran's claims.

On Sunday, former President Donald Trump announced a "Freedom Plan" on his social media platform, stating that the U.S. would assist cargo ships from non-involved nations stranded due to the Strait of Hormuz blockade. The initiative is set to begin on Monday.

He wrote: "I have instructed our representatives to do everything possible to ensure these vessels and their crews safely exit the strait." He added that all parties have agreed not to return until safe navigation and other conditions are restored in the region. No further operational details were provided.

Earlier on Sunday, Iran confirmed it had received a U.S. response to its latest peace proposal.

Reports on Friday indicated that Iran submitted an updated peace plan via Pakistani mediators, boosting investor optimism about a potential U.S.-Iran agreement. However, Trump later expressed dissatisfaction with Tehran's proposal, suggesting Iran was only seeking a deal due to "military exhaustion."

Recent expectations of easing Middle East tensions, combined with strong first-quarter earnings, have propelled stock markets to new highs. According to Bank of America strategist Nigel Tapper, the market still has upward momentum.

Tapper wrote in a client note on Friday: "The global earnings cycle remains robust, with several investment themes continuing to support equity returns worldwide."

Chris Senyek, Chief Investment Strategist at Wolfe Research, noted that strong earnings from the "Magnificent Seven" tech giants will keep artificial intelligence as a dominant market theme.

He wrote: "Solid earnings from large-cap tech companies provide further momentum for the AI narrative, likely sustaining investor interest in technology winners such as semiconductors and memory."

On Friday, both the S&P 500 and Nasdaq Composite reached new intraday and closing records. The S&P 500 rose 0.29%, while the Nasdaq gained 0.89%. The Dow Jones Industrial Average bucked the trend, falling 152.87 points, or 0.31%.

The key economic release this week is the April non-farm payrolls report, scheduled for Friday at 8:30 a.m. ET. The Dow Jones consensus estimate projects just 53,000 new jobs, significantly lower than the previous 178,000, with the unemployment rate expected to hold at 4.3%.

**Notable Stock Movers**

Energy stocks broadly advanced. APA Corp. rose nearly 1.5%, while Occidental Petroleum and Diamondback Energy each gained about 1%.

Cryptocurrency-related shares climbed. Coinbase increased 2.5%, and both Circle and BitGo rose more than 4%.

Memory-related stocks gained in premarket trading. Micron Technology, SanDisk, and Seagate Technology each rose over 3%, while Western Digital advanced 1.5%.

eBay surged nearly 9% after GameStop submitted an unsolicited, non-binding acquisition proposal valued at approximately $55.5 billion. Shares of GameStop fell more than 2.5%.

Cruise operator Norwegian Cruise Line dropped 5.5% after issuing second-quarter and full-year guidance well below market expectations.

Photonics companies Lumentum and Coherent both rose 3% after Redburn, a unit of Rothschild, initiated coverage with buy ratings.

Biopharmaceutical firm Axsome Therapeutics declined over 3.5% after reporting a larger-than-expected first-quarter loss.

Tyson Foods rose more than 2.5% following better-than-expected fiscal second-quarter results.

Advanced Micro Devices dipped nearly 1% after HSBC downgraded the stock from buy to hold, citing concerns over semiconductor supply constraints in 2026.