Former US President Donald Trump has called for the immediate resignation of Intel’s new chief executive, Lip-Bu Tan, over alleged conflicts of interest with China.

In a post on his Truth Social platform on Thursday, Trump said: “The CEO of INTEL is highly CONFLICTED and must resign, immediately. There is no other solution to this problem.”

The Trump comment came a day after Republican Senator Tom Cotton wrote to Intel’s board chair Frank Yeary to raise concerns about the security and integrity of the firm’s operations, given the new CEO’s business ties to China.

Tan has been a prolific investor in China’s tech sector over the past few decades and has ties to various leading Chinese firms. As a result, many are questioning the role of the longtime semiconductor veteran as the top executive of the US’s largest advanced chipmaker.

In his letter to Yeary, Cotton said: “The security and integrity of Intel’s operations are of national and personal concern to me. I am particularly concerned about your selection of Lip-Bu Tan as CEO. Mr Tan’s many personal and business connections to the People’s Republic of China (PRC) raise serious questions about his ability to lead Intel with undivided loyalty to the United States.”

Tan has run a global semiconductor and venture capital firm for many years. A California native, his main San Francisco-based company has several affiliates in Hong Kong and has invested tens of billions of dollars into China’s tech sector over the years.

One of the most well-known of those investments has been Semiconductor Manufacturing International Corp (SMIC), China’s largest chipmaker.

Tan has also faced increased scrutiny due to his past leadership of Cadence Design Systems, a California-based chip design software maker. Last week, Cadence said it violated US export controls by selling its chip design software to a Chinese university that has close ties to the Chinese military. The disclosure has raised further questions about Tan’s past investments and business associates.

Intel and the White House both declined to comment on Trump’s statement. Intel shares fell by 3 percent in pre-market trade in New York on Thursday morning following the former president’s comments.

Tan only took over as Intel’s CEO earlier this year after Intel’s board replaced Pat Gelsinger with Tan in March. Gelsinger was ousted as CEO in December, and Tan was elevated to the position in March to help turn around Silicon Valley’s biggest chipmaker. The company has been facing intense pressure from Taiwan Semiconductor Manufacturing Company (TSMC), the world’s largest chipmaker, as Intel has slipped behind TSMC in leading-edge manufacturing capabilities.

Intel is the last major semiconductor company headquartered in the United States that can produce advanced chips. Despite that, Intel has been slow to commercialize the latest batch of artificial intelligence chips that have emerged as the newest area of global rivalry.

The company has since been granted billions of dollars in subsidies and low-interest government loans to help it catch up to rivals like TSMC. Intel’s situation is viewed as an important part of Washington’s broader effort to wean the US from overseas chipmakers in Taiwan and South Korea. However, Intel has so far badly trailed TSMC in advanced chip manufacturing capabilities.

Tan has also signaled that there was still an outside risk that Intel could fall behind due to its current production capacity, and Intel’s continuing reliance on outside customers to buy the chips it manufactures at its most advanced technology node. In July, Tan warned that Intel would consider halting development of its most advanced manufacturing technology if it did not have a “significant external customer.”

Should Intel give up its efforts to advance to more cutting-edge nodes, it would effectively hand over the leading-edge market to TSMC. That scenario has the potential to cause ripple effects that would change the dynamics of the entire global chip market, as well as the US government’s strategy for national security in the semiconductor space.