Portugal Colonial - Seoul dives on tough day for Asia as Samsung fails to ease tech woes

Investors were unable to take up the baton from their counterparts on Wall Street, where all three main indexes reopened after a long weekend to rally on the back of gains in market heavyweights including Amazon and Apple.

The gains eased worries over a tech retreat over the past few weeks amid questions over whether the vast sums pumped into artificial intelligence will see suitable returns.

South Korean titan Samsung appeared to have answered some of those on Tuesday as it said it expected to post a jump in second-quarter operating profit of more than 1,800 percent thanks to sustained AI-driven demand for memory chips.

However, the company's shares tumbled as much as 10 percent at one point before ending down more than six percent, dragging the Kospi index down nearly five percent and deepening a rout that has hammered the market for the past two weeks.

The Kospi had more than doubled this year to a record high in June, but has since shed around 20 percent.

The results come at the start of a much-anticipated earnings season that will be closely followed for an idea about firms' outlooks for AI in light of the huge investment made in the sector.

"Strong earnings are no longer enough," wrote Saxo Markets' Charu Chanana.

"For AI-linked stocks, the market now wants strong earnings, strong guidance and clear evidence that pricing power can last."

She added: "Investors are not paying for what has already happened. They are paying for what happens next."

And Petra Capital Management's Albert Yong said the plunge suggests "investors might have already priced in solid results and are increasingly focused on the longer-term trajectory of the memory cycle".

There were also losses in Tokyo -- another tech-heavy market -- Hong Kong, Shanghai, Sydney, Taipei, Bangkok.

But there were gains in Singapore, Manila and Mumbai.

London and Paris rose but Frankfurt edged down.

Oil prices climbed more than one percent after British maritime security agency UKMTO said an "unknown projectile" had struck and caused a fire on an oil tanker off the coast of Oman near the Strait of Hormuz on Monday.

The incident occurred near one of the world's most important energy shipping routes, despite a ceasefire between the United States and Iran and efforts to secure a lasting peace agreement.

US news outlet Axios also reported late on Monday that Iran had "fired at least two missiles at commercial ships", citing two unidentified US officials. One of the officials told Axios that a second ship was also struck and had been damaged significantly.

The developments came as investors keep close tabs on US-Iranian peace talks and amid marathon funeral proceedings for late supreme leader Ayatollah Ali Khamenei.

Traders are also awaiting the release of minutes from the Federal Reserve's most recent policy meeting, hoping for fresh clues about its plans for monetary policy as it tries to battle elevated inflation.

- Key figures around 0715 GMT -

Tokyo - Nikkei 225: DOWN 2.1 percent at 68,256.96 (close)

Seoul - Kospi: DOWN 4.9 percent at 7,656.31 (close)

Hong Kong - Hang Seng Index: DOWN 0.9 percent at 23,413.69

Shanghai - Composite: DOWN 1.3 percent at 3,990.24 (close)

London - FTSE 100: UP 0.1 percent at 10,662.20

Euro/dollar: DOWN at $1.1430 from $1.1442

Pound/dollar: DOWN at $1.3377 from $1.3392

Dollar/yen: UP at 162.05 yen from 162.04 yen on Monday

Euro/pound: DOWN at 85.41 pence from 85.43 pence

West Texas Intermediate: UP 1.3 percent at $69.41 a barrel

Brent North Sea Crude: UP 1.4 percent at $72.97 a barrel

New York - Dow: UP 0.3 percent at 53,055.91 (close)

M.Carneiro--PC