By Amanda Cooper and Pete Schroeder

Global stocks fell on Tuesday as technology shares slid despite blockbuster results from Samsung Electronics, with investors remaining concerned about the sustainability of the AI-driven rally, while oil prices rose on renewed Middle East tensions.

The tech-heavy Nasdaq Composite TVC:IXIC was down 0.97% in early trading Tuesday, while the S&P 500 slipped 0.32%. The Dow Jones Industrial Average DJ:DJI was flat.

Stocks took a step backwards despite Samsung Electronics KRX:005930 forecasting a 19-fold jump in April-June operating profit to 89.4 trillion won ($58.4 billion), a third straight quarter of record operating profit for the world's largest memory-chipmaker.

Rather than reassuring investors, the results triggered heavy selling in Samsung and rival SK Hynix shares, weighing on South Korea's Kospi KRX:KOSPI and other technology-heavy Asian markets. Investors have increasingly questioned whether profit growth linked to artificial intelligence can be sustained if supply bottlenecks in key components such as memory chips ease.

"This is a record for Samsung, but rather than placate the markets, these strong results have led to fears that the AI chip sales boom cannot be sustained," Kathleen Brooks, research director at XTB, said.

Further weighing on markets was a Reuters report that Chinese startup DeepSeek was developing its own AI chip, which could reduce its reliance on other major chipmakers to train and run its AI models.

SK Hynix is due to join the Nasdaq this week in a $28 billion listing, one of the world's largest new share sales, as the chipmaker seeks to capitalise on the AI boom.

In Europe, where exposure to volatile AI-linked stocks is more limited, the STOXX 600 TVC:SXXP slipped 0.16%, as losses in semiconductor and tech stocks offset gains in oil and gas shares. Energy stocks got a lift from crude prices gaining on the back of signs that U.S.-Iran were losing momentum.

MSCI's gauge of stocks across the globe EURONEXT:IACWI was down 0.36%.

officials. The ships suffered significant damage, but there were no casualties, the report said.

Brent crude futures rose about 1.9% to $73.37 a barrel.

NATO MEETING SET TO START IN TURKEY

U.S. President Donald Trump, who has pressed Europe to boost defence spending and clashed with European leaders over the Iran war and Greenland, is due to attend a NATO meeting in Turkey beginning on Tuesday.

Trump said on Monday the U.S. would either reach a deal with Iran or "finish the job," renewing his threat of military action as Tehran projects defiance following the funeral of Supreme Leader Ayatollah Ali Khamenei.

In currency markets, the dollar index TVC:DXY, which tracks the U.S. currency against six others, was little changed at 100.87.

The yen FX_IDC:USDJPY clawed above 40-year lows to trade a touch stronger on the day at 161.9 to the dollar. Traders were alert for intervention given signs of a possible shift in strategy by Japanese authorities.

The yield on benchmark U.S. 10-year notes TVC:US10Y was up 2.4 basis points at 4.503% ahead of the release on Wednesday of the minutes of the Federal Open Market Committee's latest meeting. These may give investors more of a steer on how new Federal Reserve chair Kevin Warsh is approaching monetary policy.