Nvidia has hired one of the largest US law firms to investigate the relationship between its chief executive, Jensen Huang, and a woman alleged to be a Chinese spy. The company said on Tuesday that it had engaged New York law firm Wachtell, Lipton, Rosen & Katz, with the investigation to be led by its lawyer Joon Kim.

Nvidia stated that Kim would lead a "thorough and independent investigation". Kim is a former US Attorney for the Southern District of New York who spent several years working as a prosecutor focused on fraud and other criminal offences. Wachtell is one of the largest law firms in the US and has a number of significant clients in the technology industry, including OpenAI and Salesforce. According to sources familiar with the situation, the investigation is likely to be treated as urgent.

Jensen Huang, who co-founded Nvidia, has acknowledged having an extramarital romantic relationship. The woman, Alice Huang, also known as Huang Le, is allegedly a spy in the service of Beijing. She is not related to Jensen Huang. She was a director at Singaporean company Megaspeed, which was a customer of Nvidia and was suspected of helping to divert Nvidia chips to China. Nvidia said that concerns regarding Megaspeed had been investigated and dismissed, and that the company maintained that the US government had not notified it that Megaspeed posed an intelligence risk.

According to the New York Times, Secretary of State Marco Rubio sent a memo to senior officials in Washington in the spring of this year warning that Jensen Huang was in a close relationship with a Chinese spy. Beijing rejected the claims that Jensen Huang was a target, and the Chinese foreign ministry stated that the accusations were "aimed at smearing and slandering China".

US President Donald Trump said on Monday that he had spoken to Jensen Huang, and that the Nvidia chief had told him: "I had no idea she was a spy." Trump added that he believed him. Leaders of the Congressional Foreign Affairs Committee have requested that Jensen Huang appear at a closed briefing next week. A person familiar with the committee's request told the BBC that the Nvidia chief has not yet said whether he will comply. The committee has the authority to issue a subpoena to force him to appear before the committee if necessary.

When it announced the investigation into the relationship on Sunday, Nvidia's board said there was no reason to believe that the company's secrets or national security were compromised. The board added that the investigation would be overseen by a committee of independent directors. An Nvidia spokesperson on Tuesday declined to comment on whether Jensen Huang had engaged additional personal legal representation during the company's investigation and the separate investigation being led by the FBI.

Nvidia is widely considered one of the most important companies behind the artificial intelligence boom. It is the sole manufacturer of the key computer chip required for the successful functioning of AI tools and is the second most valuable company in the world, after Apple. Its chips have become a matter of national security for US officials who want to win the race in artificial intelligence.

The company's share price has fallen to near its yearly low, and $500 billion has been wiped off its market value since Friday. Jensen Huang's public image is closely intertwined with Nvidia, and he has become a key public figure in the development of artificial intelligence. He has claimed that the technology is a "new industrial revolution" and is on par with the advent of electricity. It is not clear whether Wachtell will be able to interview Alice Huang.