Portugal Colonial - Stock markets waver as Nvidia, Ukraine tensions urge caution

Quarterly earnings from the AI chip giant Nvidia also gave investors reason for pause, failing to match the sky-high expectations of many analysts that might underpin further tech stock gains.

But bitcoin resumed its march higher at around $97,000 on expectations that Donald Trump, spurred by cryptocurrency cheerleader Elon Musk, will bring it further into everyday use upon re-entering the White House in January.

"Will Americans be able to use crypto to pay their taxes in future? There is a bigger possibility of this happening now than before the election," said Kathleen Brooks, research director at XTB.

But the mood was decidedly more cautious in mainstream markets after this week's developments in the Ukraine war, with the US and Britain authorising Kyiv to make long-distance strikes into Russia, prompting warnings of retaliation by Moscow.

Ukraine's claim Thursday that Moscow had fired an intercontinental ballistic missile for the first time in combat added to uncertainty over what might come next.

Oil prices also rose "as geopolitical tensions outweighed concerns over rising US crude supplies", said Matt Britzman, senior equity analyst at Hargreaves Lansdown.

"Geopolitical fears have also sent gold higher in recent sessions as investors look for some safety as Russia-Ukraine tensions escalate," he added.

Asian stocks had mostly fallen earlier Thursday under pressure from Nvidia's earnings, though analysts said profit-taking was unlikely to dampen enthusiasm for the key AI player.

"The negative market reaction to Nvidia's results suggests investors are now focusing on the minutiae rather than the big picture," said Dan Coatsworth, investment analyst at AJ Bell.

"That's a natural evolution as the more people zoom in on a company, the more they learn about it, and the more granular detail they want."

Elsewhere on the corporate front, shares in Indian conglomerate Adani Group tanked after US prosecutors charged its owner Gautam Adani with handing out more than $250 million in bribes for key contracts.

Flagship operation Adani Enterprises dived almost 20 percent, while several of its subsidiaries -- from coal to media businesses -- lost 10 to 20 percent.

- Key figures around 1455 GMT -

New York - Dow: UP 0.2 percent at 43,489.58 points

New York - S&P 500: DOWN 0.1 percent at 5,907.37

New York - Nasdaq: DOWN 0.4 percent at 18,887.91

London - FTSE 100: UP 0.5 percent at 8,123.38

Paris - CAC 40: DOWN 0.1 percent at 7,190.62

Frankfurt - DAX: UP 0.3 percent at 19,065.93

Tokyo - Nikkei 225: DOWN 0.9 percent at 38,026.17 (close)

Hong Kong - Hang Seng Index: DOWN 0.5 percent at 19,601.11 (close)

Shanghai - Composite: UP 0.1 percent at 3,370.40 (close)

Euro/dollar: DOWN at $1.0531 from $1.0545 on Wednesday

Pound/dollar: DOWN at $1.2632 from $1.2652

Dollar/yen: DOWN at 154.09 yen from 155.45 yen

Euro/pound: UP at 83.38 pence from 83.33 pence

Brent North Sea Crude: UP 1.3 percent at $74.07 per barrel

West Texas Intermediate: UP 1.3 percent at $70.04 per barrel

S.Pimentel--PC