The FBI is investigating Nvidia CEO Jensen Huang’s affair with an alleged Chinese government agent, US President Donald Trump says.

“I know the FBI is looking into it in terms of something else, and I think that he’ll be in good shape,” Trump said at the White House on Monday (local time).

Trump suggested he’d taken the extraordinary step of directly involving himself in a counterintelligence investigation, a sign of his friendly relationship with Huang and the possible geopolitical stakes.

“I did speak to him today just to see if he’s feeling all right, how you’re doing,” Trump said. “He said he had absolutely no idea that the person in question was a spy.”

Next week, Trump is expected to meet Chinese leader Xi Jinping in Shenzhen, China, at the Asia-Pacific Economic Cooperation summit. He was noncommittal about bringing up the situation with Xi.

“No, I don’t think so,” Trump said. “I mean, maybe. I’m sure President XI will ask me about it. I just know Jensen very well. I just think he’s a very honourable man.”

China has denied engaging in an attempt to ensnare Huang, saying the spying allegations were unsubstantiated and a smear campaign against Beijing.

Huang has acknowledged he had been intimate with a business executive, issuing an apology to his wife and to the company in an open letter posted on Nvidia’s website.

He did not name the woman although The NY Times has reported he developed a close relationship with a Chinese citizen named Alice Huang. She ran a company that last year faced claims it was illicitly shipping advanced Nvidia computer chips into China.

Nvidia announced it was conducting an independent investigation into reports Huang was the “target of a foreign intelligence effort.”

The New York Times reported that US intelligence determined that the woman was gathering information for Beijing.

“I support the investigation and will cooperate fully. I love our country and our company. I am committed to protecting NVIDIA and supporting America’s national security,” Huang said in his letter.

The investigation into whether Nvidia’s CEO was the target of a foreign intelligence effort is raising questions about the future of the company, which became one of the world’s most valuable firms by providing technology that has powered the AI boom.

Nvidia stock has shed roughly 11 per cent of its value since last Wednesday.

On Monday, a Chinese spokesperson rejected claims it used the woman as a spy.

“The so-called Chinese spy allegation is unsubstantiated. It is nothing but smears against China,” Ministry of Foreign Affairs spokesperson Guo Jiakun said.

Beijing earlier had dismissed The NY Times report. The newspaper said Alice Huang was a former executive of a Singapore-based data centre company called Megaspeed International, whose website prominently touts its partnership with Nvidia.

Nvidia is one of the world’s most valuable publicly traded companies, alongside Apple and Microsoft. Its sales of computer chips to China have at times been targeted by US regulators seeking to limit Beijing’s access to such technology.

Huang and Nvidia have a critical role in the AI industry as many of the world’s leading developers rely on the company’s specialised chips to power their systems.

Huang has also helped persuade Trump to take a lighter touch on regulating AI, arguing existing laws could cover any security issues stemming from the technology and that individual companies should behave responsibly with the products they develop and release.

-AAP