President Donald Trump has called for Intel’s new chief executive, Lip-Bu Tan, to resign over what he described as “highly conflicted” interests.

“The CEO of INTEL is highly CONFLICTED and must resign, immediately. There is no other solution to this problem,” Trump tweeted Thursday on Truth Social.

The statement, which was devoid of elaboration, came after Republican Senator Tom Cotton on Tuesday wrote to Intel board chairman Frank Yeary with “concern about the security and integrity of Intel’s operations” because of Tan’s business ties to China.

Cotton pointed to Tan’s status as a prolific investor in Chinese tech companies over the past two decades and said those links posed a “disturbing risk to the American leadership of the semiconductor industry that Intel has long embodied as the nation’s largest advanced chipmaker.”

Tan, a Silicon Valley veteran with nearly three decades of experience in semiconductors and venture capital, is the founder and chief executive of Micron Technology, a San Francisco-based investment firm with Hong Kong offices that has poured money into Chinese tech companies.

Past investments include Semiconductor Manufacturing International Corp (SMIC), China’s biggest chipmaker.

Tan is also a former chairman of Cadence Design Systems, a California-based chip design software maker, which last week said it had sold some of its products to a Chinese university with ties to China’s military, in violation of U.S. export controls.

Cadence’s disclosure that it had failed to secure a required license for the sale to Fudan University earlier this year has added scrutiny to Tan’s connections and business past.

Intel and the White House did not immediately respond to requests for comment on Trump’s post. In New York, the company’s shares were down 3 percent in pre-market trading on Thursday after the news.

Tan was named CEO of Intel in March after a company board vote, which also included him replacing his predecessor, Pat Gelsinger, who was forced out as CEO last December.

Intel, at the time of Tan’s appointment, was under pressure as the flagship of the U.S. semiconductor industry after it had been surpassed by Taiwan Semiconductor Manufacturing Company (TSMC) as the world’s largest chipmaker by volume and lost momentum in the global rush for the advanced technologies that would be central to the artificial intelligence revolution.

Intel is in many ways uniquely positioned as the only U.S.-headquartered company with the capacity to produce leading-edge chips. But while the company is benefiting from billions of dollars in subsidies and loans, the boom in AI chips has largely passed it by.

Intel’s position means that its new CEO faces a daunting task. He must do more than guide Intel in the next era of chipmaking. He must figure out how to retain U.S. leadership in an area that was once a Silicon Valley stronghold but that is increasingly a competition between Washington and Beijing.

Intel is at a turning point. Tan’s appointment came after he had ousted his predecessor, Pat Gelsinger, who was pushed out as CEO last December. But Intel is under pressure, both from the company’s slide and from Washington as part of the U.S. government’s effort to boost domestic manufacturing of semiconductors and reduce the U.S. economy’s dependence on chipmakers based in Taiwan and South Korea.

The $52 billion in government subsidies and loans that Intel has received under President Joe Biden’s Investing in America plan is only a start. The funding is part of a wider Washington drive to stimulate domestic semiconductor manufacturing. Intel’s faltering has meant Tan faces pressure to deliver before the next phase of semiconductor subsidies is even approved.

In July, Tan, speaking at an industry conference, warned that without a “significant external customer,” Intel’s next-generation chip manufacturing tech could be put on “pause.”

If Intel were to do so, then TSMC would have a near monopoly in leading-edge chipmaking, Tan said. The resulting impact would be “not just for the semiconductor industry, but for national security.

Tan’s cost-cutting measures to restore Intel to profitability have caused alarm about the company’s future, even as its share price has jumped.

Senator Cotton made clear that Intel’s status as a taxpayer-subsidized firm, as well as one with national security implications, places greater demands on its management. “Intel is required to be a responsible steward of American taxpayer dollars and to comply with applicable security regulations,” Cotton wrote. “Mr Tan’s associations raise questions about Intel’s ability to fulfill these obligations.”