President Donald Trump has called on the newly minted chief executive of Intel, Lip-Bu Tan, to immediately step down from his post. Trump said Tan is “highly conflicted” in a post on his Truth Social network.

Tan was named CEO of Intel late last month. Trump criticized the veteran semiconductor industry executive in a post on Thursday, April 27.

“The CEO of INTEL is highly CONFLICTED and must resign, immediately. There is no other solution to this problem,” Trump wrote in the post.

Tan, a mainstay of Silicon Valley who runs an investment firm in San Francisco and two firms in Hong Kong, has pumped millions of dollars into China’s tech sector over the years, turning him into one of the country’s most prolific investors. Last year, Senator Tom Cotton of Arkansas, a member of Trump’s party, Republican, sent a letter to Intel’s board of directors, Frank Yeary. It raised “concern about the security and integrity of Intel’s operations,” according to Cotton, who had selected Tan as his CEO at a time when relations between the United States and China had deteriorated.

In a letter to Intel board chair Yeary last month, Cotton pointed to Tan’s investments in Chinese semiconductor, artificial intelligence, and cloud computing companies and called into question Tan’s appointment as Intel’s CEO. China is home to Intel’s most important competition, and Tan is a key driver of its rise.

Intel, its board, and Tan himself have not commented on Trump’s post. But Tan’s new boss at Intel, who had the privilege of selecting Trump’s successor after he left office, had made similar comments days earlier. Trump’s criticism comes as Intel, the United States’ most advanced chipmaker, is also under pressure to move faster. It has been building a new factory in China since 2019 to compete with TSMC, which is largely owned by the Taiwanese government.

Intel has agreed to pay up to $25 billion for an unlisted software chip firm, Cadence Design Systems. Tan was formerly Cadence’s CEO. In the letter, Cotton refers to China’s TSMC as the United States’ most important competitor. Sen. Cotton is concerned about Tan’s ties to China and its military.

The company’s shares fell 3 percent in pre-market trade in New York on Thursday morning following Trump’s post. Tan took the helm as Intel’s CEO in March, months after the company’s board voted to remove his predecessor, Pat Gelsinger, from his post in December. Intel’s new CEO will have to reverse its fortunes against TSMC. Both companies make chips but focus on different parts of the market.

Intel Corp on Thursday named veteran venture capitalist Lip-Bu Tan its new chief executive as it struggles to regain its footing after losing ground in the global semiconductor industry. Tan replaces former CEO Pat Gelsinger, who was forced out in December.

Intel shares were down 2.6% at $46.87 in pre-market trading. Tan’s selection comes at a particularly precarious time for Intel, which has been scrambling to narrow the gap with Taiwan Semiconductor Manufacturing Co. Ltd.

Intel has struggled to keep pace with TSMC, the world’s largest contract chipmaker, which has also attracted billions of dollars in state subsidies in recent years. Tan, who has spent most of his career in the semiconductor and venture capital industries, runs a venture capital firm in San Francisco and two in Hong Kong, has been a prolific investor in China.

Intel’s fortunes have been closely watched in Washington as it attempts to boost U.S. semiconductor manufacturing in the face of Taiwan and South Korean chipmakers like TSMC. Tan has warned that Intel could slow its most advanced manufacturing technology if it does not have a “significant external customer” to subsidize its cost. If Intel were to abandon its most advanced technology, TSMC would effectively be left alone in a league of its own.