Former U.S. President Donald Trump has called on the new chief executive of Intel to step down immediately, blasting Lip-Bu Tan as “highly conflicted.”

In a statement posted to the social media app Truth Social on Thursday, Trump said: “The CEO of INTEL is highly CONFLICTED and must resign, immediately. There is no other solution to this problem.” The four-sentence post, however, did not elaborate on why Tan was “highly conflicted.”

Tan was appointed as the new chief executive of Intel in March this year after the company’s board decided to replace outgoing CEO Pat Gelsinger. The move came after Gelsinger, who was Intel’s former chief technology officer, was abruptly removed in December last year.

Intel did not respond to a request for comment on Trump’s statement. The White House also did not respond to a query.

Tan, a well-known name in the semiconductor industry for his long career in venture capital, is a U.S.-Singaporean businessman and was born in Malaysia. Before joining Intel, he founded technology venture capital firm Aveca, with offices in San Francisco and Hong Kong. The firm has invested in a number of Chinese companies, including SMIC, China’s largest chipmaker.

Tan was also the CEO of Cadence Design Systems, a California-based company that provides software to computer chip designers, until 2020. Last week, Cadence admitted that it violated U.S. export controls by selling chip design software to East China Normal University. The school has been identified by the U.S. Commerce Department as having close ties with the People’s Liberation Army (PLA).

Tan took over as the CEO of Intel when the company was at its lowest point in its history, struggling to catch up with Taiwan Semiconductor Manufacturing Company (TSMC), the world’s largest semiconductor foundry. Intel is Silicon Valley’s last hope of remaining at the forefront of the global chip race as the only U.S.-headquartered company with the capacity to make cutting-edge chips. However, Intel is falling behind in the race for artificial intelligence (AI) chips, the new battleground in the global chip industry.

In July, Tan, under immense pressure to turn the company around, warned that if Intel failed to find a “significant external customer” to use the firm’s new manufacturing technology, it would have to consider scaling back the program. If the company decided to withdraw from the manufacturing technology, the world would only have one advanced chipmaker, TSMC. That prospect would be disastrous for the U.S., given the strategic importance of semiconductors to American national security.

Tan also faces a credibility test as Intel has been awarded billions of dollars in subsidies and loans by the U.S. government to help it develop a more advanced chip manufacturing process. Part of a broader push by Washington to bolster domestic chip production and reduce U.S. reliance on foreign chipmakers in Taiwan and South Korea, Intel has lagged far behind TSMC in leading-edge chip manufacturing.

Amid all these problems, Intel’s stock has been performing poorly in the market. On Thursday, Trump’s post only accelerated the bleeding, with Intel’s share price falling by 3 percent in pre-market trade in New York.

Tan’s ties to China have not gone unnoticed by some of his colleagues on Capitol Hill. Republican Senator Tom Cotton sent a letter to Intel’s board of directors chair Frank Yeary on Tuesday, warning the company about Tan’s close ties to China. In the letter, Cotton wrote: “In light of your upcoming appointment of Lip-Bu Tan as Intel’s new CEO, I write to you with concern about the security and integrity of Intel’s operations.”

Cotton also went on to point out that Tan was a “persistent investor” in Chinese tech companies, even as Intel was forced to outsource its technology to Chinese chipmakers as it fell behind in cutting-edge manufacturing.

“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,” Cotton wrote.