Republican leaders of three US House committees have asked Nvidia chief executive Jensen Huang to testify privately about an extramarital relationship that has prompted questions about national security. House Foreign Affairs Committee Chair Brian Mast said he was ready to issue a subpoena if Huang failed to respond by the end of Wednesday.

Huang, 63, has acknowledged having an affair while leading the US technology company. Media reports identified the woman as Alice Huang, a former executive at Singapore-based Megaspeed who is accused of having ties to Chinese intelligence. The New York Times reported that US intelligence officials believe she was recruited to collect information about the Nvidia chief and encourage him to seek fewer restrictions on chip exports to China.

No publicly available evidence has established that Alice Huang obtained sensitive Nvidia information or influenced Jensen Huang’s decisions. US intelligence agencies have also not publicly released evidence supporting the allegation that she worked for Chinese intelligence. China has rejected the espionage accusations, with Foreign Ministry spokesperson Guo Jiakun describing them on Monday as groundless and a smear campaign.

Jensen Huang apologised to his family and Nvidia employees in a statement on Sunday. Nvidia opened an independent investigation and said it had no reason to believe company secrets or national security had been compromised. By Wednesday, however, media reports suggested the company was preparing to separate from Huang, who co-founded Nvidia more than three decades ago.

President Donald Trump confirmed on Monday that the Federal Bureau of Investigation was examining the matter, while continuing to support Huang and calling him an “honourable guy”. Republican Senator Kevin Cramer urged Huang to resign on Tuesday, telling Politico that the possibility of extortion was too significant given the sensitivity of Nvidia’s chips. Huang has shown no indication that he intends to step down.

Nvidia’s advanced processors underpin much of artificial intelligence technology, making the company central to US-China technological competition. Washington has limited exports of some of its most advanced chips to China since 2022 because of concerns about military and intelligence uses. Huang had already advocated easing those controls, arguing that restricting access to US products would strengthen China’s own chip industry.

Scrutiny also extends to Nvidia’s dealings with Megaspeed, which purchased more than $4.8 billion in its chips over roughly two years. Megaspeed has faced an investigation into allegations that it helped Chinese companies obtain restricted chips, an accusation it denies. Ryan Fedasiuk, a Foundation for American Innovation fellow, cited reporting that Nvidia contacted the Commerce Department about its Megaspeed investigation. He also said Nvidia appeared to substantially understate the value of those sales in government disclosures, raising questions about whether the relationship affected its actions.

Experts have identified several categories of potentially sensitive information, without establishing that any were disclosed. Council on Foreign Relations senior fellow Jessica Brandt highlighted designs for chips intended for China, research and development, and discussions with policymakers. Fedasiuk also pointed to future products, internal operations, customers and Huang’s relationships with Trump and senior White House officials as possible areas of concern.