New York (AFP) - A slump in high-flying technology stocks dragged down global markets Tuesday, with Wall Street tumbling again on valuation concerns and persistent worries over huge AI outlays.

The rout that began on US markets Monday took a heavy toll in Asia, with South Korea’s Kospi slumping 10 percent on heavy selling of SK hynix and Samsung.

The tech-rich Nasdaq slumped more than two percent behind big drops in semiconductor shares. Both Micron Technology and Sandisk dove more than 13 percent.

Angelo Kourkafas from Edward Jones described the pullback as prompted by concerns that stock valuations have gotten out of hand, rather than a rethink in the need for the artificial intelligence boom that has lifted to record heights.

“There are some concerns about sentiment valuations and positioning, I would say, more so rather than a notable shift in the AI fundamental story,” Kourkafas said.

“The market likes to take two steps forward, one step back, and that’s the step-back phase.”

After falling the last three days, SpaceX early in the session retreated below $150 – the level at which it began trading on June 12, its first day on the Nasdaq.

But SpaceX shares later reversed course, finishing at $156.11, up 1.0 percent for the day.

Still, the announcement of a bond offering by Elon Musk’s rocket company and satellite operator added to investor unease.

SpaceX “jumping on the bond train to fund excessive AI and infrastructure spending revives earlier concerns that Big Tech may be spending too much on AI infrastructure and increasingly financing that spending through debt,” said Ipek Ozkardeskaya, senior analyst at Swissquote bank.

Share prices of South Korean chip giants SK hynix and Samsung tumbled more than 12 percent to drag the Kospi index down 10 percent, having finished Monday at a record high.

“When you have markets that go up in a straight line… they tend to experience sharp moves in the opposite direction at unpredictable times,” said Steve Sosnick of Interactive Brokers.

“This is what happens when markets get stretched.”

Tokyo also took a beating, shedding 3.6 percent, with tech investment titan SoftBank down more than 10 percent, Tokyo Electron 6.2 percent lower and Advantest off more than two percent.

Oil prices slipped, adding to recent falls as more tankers return to the Strait of Hormuz following a US-Iran deal aimed at ending the Middle East war.

Traffic on Monday through the Strait of Hormuz reached the highest level since the start of the Middle East war, according to maritime tracking data from analytics platform Kpler.

A temporary suspension of US sanctions against Iran during their negotiations also raised hopes that more oil would be hitting the market soon.

Brent North Sea Crude shed another 1.1 percent to $77.08 a barrel around 1530 GMT and West Texas Intermediate dropped similarly to $73.21.

Earlier in the conflict they had soared past the $110 mark.

- Key figures around 2020 GMT -

New York - Dow: DOWN 0.1 percent at 51,666.84 (close)

New York - S&P 500: DOWN 1.4 percent at 7,365.46 (close)

New York - Nasdaq: DOWN 2.2 percent at 25,587.04 (close)

London - FTSE 100: DOWN 0.1 percent at 10,428.85 (close)

Paris - CAC 40: DOWN 0.7 percent at 8,340.71 (close)

Frankfurt - DAX: DOWN 1.0 percent at 24,893.58 (close)

Seoul - Kospi: DOWN 10.0 percent at 8,203.84 (close)

Tokyo - Nikkei 225: DOWN 3.6 percent at 69,788.38 (close)

Hong Kong - Hang Seng Index: DOWN 1.8 percent at 23,336.28 (close)

Shanghai - Composite: DOWN 1.4 percent at 4,106.25 (close)

Brent North Sea Crude: DOWN 1.1 percent at $77.08 a barrel

West Texas Intermediate: DOWN 0.9 percent at $73.21 a barrel

Euro/dollar: DOWN at $1.1383 from $1.1429 on Monday

Pound/dollar: DOWN at $1.3196 from $1.3251

Dollar/yen: DOWN at 161.52 yen from 161.57 yen

Euro/pound: DOWN at 86.23 pence from 86.26 pence

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