President Donald Trump confirmed on Monday that the Federal Bureau of Investigation is actively investigating Nvidia CEO Jensen Huang. The federal probe follows a disclosure by the chipmaker late Sunday that it had begun an internal review of Huang’s extramarital affair with a woman identified as an alleged Chinese intelligence officer.

At an impromptu press briefing at the White House, Trump stated that he had spoken with Huang earlier in the day. The president explained that the purpose of the call was to check on the executive’s well-being. Trump quoted Huang as telling him that he had absolutely no idea the woman in question was a spy. The president added that he genuinely believed Huang’s account of the situation.

Nvidia’s board of directors announced on Sunday that it was launching an independent investigation. The board cited recent media reports indicating that Huang had been the target of a foreign intelligence effort. Simultaneously, Huang issued a personal statement acknowledging that he had been unfaithful to his wife. He also extended his apologies to employees of the company.

Trump expressed personal surprise at the revelations, describing Huang as a high-quality individual. The president indicated that he wants Huang to remain the leader of the second largest public company in the world. This marked the second time in two days that Trump voiced support for Huang’s continued tenure as CEO. Trump expressed hope that the situation would resolve without major issues for the company.

According to people familiar with the matter who spoke to NBC News on Sunday, U.S. intelligence agencies determined that Alice Huang, the woman alleged to have been involved with Jensen Huang, was a Chinese spy. It was noted that the two individuals are not related by blood or marriage.

Nvidia spokespeople did not immediately respond to requests for comment on Monday following the president’s remarks. The company had previously stated that Huang would continue to serve as CEO despite the disclosures regarding the affair and the foreign intelligence interest.

The news had a noticeable impact on the stock market. Nvidia shares closed down 4.2 percent in Monday’s trading session. This decline went against the general momentum of the broader market. The stock finished as the worst performing company in both the Dow Jones Industrial Average and the Nasdaq composite index.

The situation has also attracted significant attention from members of Congress. Representative Hakeem Jeffries, a Democrat from New York, called for a full briefing on the issues surrounding Nvidia on Monday. Jeffries is expected to be elected as the next speaker of the House in January.

Senators Elizabeth Warren from Massachusetts and Jim Banks from Indiana also weighed in with a joint statement. The bipartisan pair argued that Congress should take decisive action regarding the oversight of companies linked to artificial intelligence. They wrote that the disclosures made by Nvidia and Huang make national security concerns more urgent and raise important questions that the company must answer.