Donald Trump has called for the immediate resignation of Intel’s new chief executive, Lip-Bu Tan, after the former U.S. president described the semiconductor industry veteran as “highly conflicted.”

“In the interest of national security, the CEO of INTEL is highly CONFLICTED and must resign immediately. There is no other solution to this problem,” Trump wrote in a post on his Truth Social platform on Thursday. The statement from Trump, who left office more than two years ago, offered no further explanation about what Tan’s alleged conflicts of interest were.

The comments follow Republican Senator Tom Cotton’s letter to Intel’s board chair, Frank Yeary, on Tuesday, raising “concern about the security and integrity of Intel’s operations” in light of Tan’s extensive business relationships in China. “Mr Tan’s history as a prolific investor in Chinese technology companies raises concerns that he may not be able to effectively lead the world’s preeminent advanced chipmaker without creating unacceptable risks to U.S. national security,” Cotton wrote in the letter, first reported by The Wall Street Journal.

Tan, who assumed leadership of Intel last month after the company’s board ousted his predecessor in December, is a Silicon Valley fixture. For decades, the chip industry veteran has built a global footprint in the semiconductors and venture capital worlds. His San Francisco-based venture firm and another company he runs in Hong Kong have collectively invested in hundreds of Chinese technology companies. In the past, Tan has also made investments in Semiconductor Manufacturing International Corp (SMIC), China’s largest chipmaker.

Tan has also been in the crosshairs of increased scrutiny in recent days because of his former role as CEO and chairman of Cadence Design Systems, a chip design software company based in California. Last week, Cadence disclosed that it violated U.S. export controls in a deal with a Chinese university with close ties to the People’s Liberation Army. The disclosure about Cadence’s Chinese transaction was made on the same day that Tan was announced as Intel’s CEO.

Intel and the White House declined to comment on Trump’s post. But Intel’s stock price quickly reacted to the development, falling 3 percent in pre-market trading in New York on Thursday morning.

Intel changes leadership at a critical time for the Silicon Valley giant

Intel at this point is the only U.S.-headquartered company with the know-how to produce advanced semiconductors. However, even with this home-field advantage, Intel has thus far been largely absent from the artificial intelligence boom in chips, the next front in the global chip race.

Intel has received billions of dollars in government subsidies and loans to help jumpstart its competitiveness. The handouts are part of Washington’s larger push to incentivize semiconductor manufacturing within the U.S. and away from reliance on chipmakers in Taiwan and South Korea. Still, Intel has so far significantly lagged behind TSMC in cutting-edge chipmaking, and the company’s decision to fire Gelsinger and appoint Tan has led to concern about Intel’s ability to keep up the fierce pace in an AI-driven world.

Last month, Tan said the company could “end up terminating development” of its next-generation manufacturing technology unless it finds a “significant external customer.” In other words, unless Intel can get additional business to use its most advanced chipmaking tech, it may pull the plug. If that were to happen, TSMC would essentially have a monopoly on leading-edge chipmaking, with serious implications not just for the global semiconductor industry but for U.S. national security as well.

Uncertainty around Intel’s plans in this area has coincided with Tan’s cost-cutting moves to restore profits at Intel. The measures have been welcomed by some, but they have also further stoked fears about Intel’s trajectory.

Cotton raised similar concerns in his letter to Intel’s board chair, writing: “Intel is required to be a responsible steward of American taxpayer dollars and to comply with applicable security regulations. Mr Tan’s associations raise questions about Intel’s ability to fulfill these obligations.”

Intel, for its part, is in a difficult spot with Tan, a veteran of the industry and the semiconductor business who has long-standing ties to Asia. It is a globalized semiconductor economy, and Tan’s connections are an asset. At the same time, his investments and relationships in China, combined with Cadence’s recent export control violation, are a gift for critics who view him as a risk for U.S. technology rivalry with China.

Tan now has to deal with the additional headache of Trump politicizing Intel’s internal struggles, even as the U.S. is working to assert itself in the global chip supply chain and challenge China’s ambitions in the AI semiconductor space.

Intel’s stock price may have already factored in some of the turbulence, but there is little doubt that Tan, for better or worse, will now be put under the microscope by investors, regulators, and even members of Trump’s political party. In this political and economic environment, Intel must carefully navigate the debate around Tan to avoid additional uncertainties around its technology leadership and strategy.

Should Intel stick with Tan, his performance will be closely scrutinized in the coming months and years, as TSMC’s chipmaking technology gap and China’s quest to dominate the AI semiconductor industry loom large.