Intel Corp (NASDAQ:INTC, ETR:INL) shares fell 3.4% to $19.72 after Donald Trump has called for the resignation of new chief executive, Lip-Bu Tan.
In a social media post, the US President alleged that Tan "is highly conflicted and must resign, immediately. There is no other solution to this problem."
No details were put forward by Trump of the alleged conflicts of interest.
However, it follows a letter from Republican Senator Tom Cotton to the board of the US company this week where he expressed "concern about the security and integrity of Intel’s operations" and Tan’s investments in Chinese chip firms.
An Intel spokesperson said: "Intel and Mr Tan are deeply committed to the national security of the United States and the integrity of our role in the U.S. defense ecosystem."
Tan is a longtime technology investor via his San Francisco-based Walden Catalyst Ventures firm, including in US, Chinese and Hong Kong companies, including China's Semiconductor Manufacturing International Corp.
He was also CEO of Cadence Design Systems Inc (NASDAQ:CDNS) from 2009 to 2021, amidst a 19-year career at the semiconductor design group.
As Intel is receiving federal funding under the Secure Enclave initiative, the letter from Cotton questioned Tan's disclosures and ties to Chinese companies.
"Intel is required to be a responsible steward of American taxpayer dollars and to comply with applicable security regulations," the letter said. "Mr. Tan's associations raise questions about Intel's ability to fulfill these obligations."