Stock markets struggled on Tuesday as US President Donald Trump reignited trade war fears after he called for fresh curbs on Chinese investments including in the tech sector.

London equities rose while Paris and Frankfurt struggled for direction, with defense and banking stocks faring particularly well. 

That followed a weak session across Asia and in New York. 

Global markets were responding to an "unease over looming US tariff policies and their potential ripple effects on global growth and inflation," said Matt Britzman, senior equity analyst at Hargreaves Lansdown.

Trump said on Monday that he plans to proceed with tariffs on Canada and Mexico once a 30-day suspension expires next week.

Levies were announced against countries in January but had been delayed to allow for negotiations. Tariffs on Chinese goods went ahead without a grace period.

The announcement came after Trump signed a memo at the weekend calling for curbs on Chinese investments in industries including technology and critical infrastructure, healthcare and energy.

The developments fanned tensions between the world's top economic superpowers and added to concerns about the possibility of another debilitating trade war amid growing uncertainty about the global outlook.

"Trump’s first term as US president was defined by trade wars. We might now be looking at his second term as being a tech war, with the world battling China," said AJ Bell investment director Russ Mould.

Hong Kong dropped more than one percent, with Alibaba and e-commerce rival JD.com off more than three percent and Tencent losing nearly three percent. 

Shanghai and Tokyo stock markets were also in the red.

The losses followed a broadly negative day in New York, where tech giants have hit a wall since China's DeepSeek unveiled a chatbot that upended the AI industry and led traders to reassess their recent vast investments.

It also came ahead of the release of earnings from market darling Nvidia, which will be closely watched for its views on the outlook in light of the Chinese startup's arrival.

Seoul retreated as the South Korean central bank cut its economic growth outlook and lowered interest rates amid fears over the US tariffs and the fallout from President Yoon Suk Yeol's brief declaration of martial law in December.

Bitcoin fell back below $90,000 for the first time in a little more than a month as the optimism over expected Trump deregulation for the crypto market ebbs away.

The sector has also been hit by the recent $1.5 billion hack of Dubai-based cryptocurrency exchange Bybit, representing the biggest crypto theft in history, as well as a memecoin scandal in Argentina.

In company news, shares in British consumer goods giant Unilever fell around two percent after chief executive Hein Schumacher stepped down after less than two years at the helm. 

Key figures around 1100 GMT

London - FTSE 100: UP 0.3 percent at 8,686.25 points

Paris - CAC 40: DOWN 0.1 at 8,081.10

Frankfurt - DAX: DOWN 0.1 percent at 22,396.74 

Tokyo - Nikkei 225: DOWN 1.4 percent at 38,237.79 (close)

Hong Kong - Hang Seng Index: DOWN 1.3 percent at 23,034.02 (close)

Shanghai - Composite: DOWN 0.8 percent at 3,346.04 (close)

New York - Dow: UP 0.1 percent at 43,461.21 (close)

Euro/dollar: UP at $1.0473 from $1.0468 on Monday

Pound/dollar: UP at $1.2625 from $1.2623

Dollar/yen: UP at 149.79 from 149.76 yen

Euro/pound: UP at 82.97 pence from 82.91 pence 

West Texas Intermediate: FLAT at $70.71 per barrel

Brent North Sea Crude: UP 0.3 percent at $74.24 per barrel