Nvidia has launched an independent investigation into whether chief executive Jensen Huang was targeted by a Chinese intelligence operation, after the billionaire admitted to an extramarital relationship that has raised concerns about potential national security implications.

The chipmaker announced on Sunday that a committee of independent directors, supported by external legal counsel, would oversee the inquiry following reports that Huang had a relationship with Alice Huang, a former executive at Singapore-based data centre company Megaspeed.

The New York Times reported in October that US authorities had concluded Alice Huang was a Chinese intelligence asset who passed information to Beijing. She is unrelated to the Nvidia chief and has previously been investigated over allegations that Megaspeed helped Chinese companies obtain advanced chips in breach of US export controls.

Nvidia said its board had no reason to believe US national security or company secrets had been compromised. It added that the investigation would examine all available information, while confirming that Huang supported the review and would continue leading the business.

In a message to employees on Sunday, Huang admitted he had been unfaithful to his wife and apologised for the impact on his family. "There is no excuse for what I did. I am deeply sorry," he said, adding that he remained committed to the company and would work to regain the confidence of colleagues, shareholders and business partners.

The investigation comes as Nvidia faces mounting scrutiny over its relationship with Chinese customers and the security implications of exporting advanced artificial intelligence processors. US export controls introduced in 2022 have sought to restrict Beijing's access to the most sophisticated chips, which Washington considers strategically important for economic and military competition.

Republican lawmakers in the US House of Representatives have requested a closed-door briefing from Huang on 18 November covering his relationship with Alice Huang and Nvidia's safeguards against foreign espionage. The request follows concerns raised by congressional committee leaders about China's potential access to sensitive American technology.

President Donald Trump defended the Nvidia chief on Sunday, describing him as an honourable person and saying he had not discussed the allegations with him. US Secretary of State Marco Rubio declined to comment.

The controversy adds pressure to Nvidia during a period of volatility for technology stocks, with investors questioning the sustainability of spending on artificial intelligence infrastructure. The company's market valuation stood at approximately $4.5 trillion, while its shares had surrendered their gains for the year.

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