* Samsung sees 19-fold increase in April-June operating

profit

* Nasdaq 100 E-minis down 1.2%, S&P 500 E-minis dip 0.3%

* Brent crude up 1% after US-Iran peace talks appeared to

stall

(Updates throughout)

By Amanda Cooper

LONDON, July 7 (Reuters) - Global stocks fell on Tuesday as

technology shares slid despite blockbuster results from Samsung

Electronics ( SSNLF ), with investors remaining concerned about the

sustainability of the AI-driven rally, while oil prices rose on

renewed Middle East tensions.

Samsung Electronics ( SSNLF ) forecast a 19-fold jump in

April-June operating profit to 89.4 trillion won ($58.4

billion), marking 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 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.

Morgan Stanley said in a note dated Monday that recent

weakness in U.S. semiconductor stocks signalled a broadening of

market gains, with investors likely to turn towards AI

hyperscalers as well as consumer discretionary, transport and

biotechnology shares.

SK Hynix is due to enter 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.

Its shares, which were up as much as 350% this year at their

peak two weeks ago, have since fallen about 30% amid a broader

sell-off in global chip stocks.

In Europe, where exposure to volatile AI-linked stocks is

more limited, the STOXX 600 rose 0.1%, supported by

gains in oil and gas shares as crude prices edged higher amid

signs that U.S.-Iran peace talks were losing momentum.

Adding to market concerns, Iran's Revolutionary Guards fired

at least two missiles at commercial ships transiting the Strait

of Hormuz on Monday, Axios reported, citing two U.S. officials.

The ships suffered significant damage, but there were no

casualties, the report said.

Brent crude futures rose about 1% to $72 a barrel.

U.S. S&P 500 E-minis dipped 0.3%, Nasdaq 100

E-minis retreated 1.2% and Dow E-minis were

down 0.02%.

NATO MEETING

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 former

Supreme Leader Ayatollah Ali Khamenei.

In currency markets, the dollar index, which tracks

the U.S. currency against six others, was little changed at

100.88. The euro was down 0.03% at $1.1436.

The yen rebounded from beyond 162 per dollar, near

40-year lows, and was last up 0.17% at 161.79 per dollar.

Traders remained alert for intervention amid signs of a possible

shift in strategy by Japanese authorities.

Japanese government bond yields fell from multi-decade highs

after a sale of super-long-term debt attracted strong demand.

The yield on benchmark U.S. 10-year notes rose

1.62 basis points to 4.495%, from 4.479% late on Monday.

Investors will get a further indication of how new Federal

Reserve Chair Kevin Warsh is approaching monetary policy when

minutes from the Federal Open Market Committee's latest meeting

are released on Wednesday, the first set published under his

leadership.

(Additional reporting by Satoshi Sugiyama in Tokyo. Editing by

Lincoln Feast and Mark Potter)