In the letter, Warren wrote that Musk’s actions as the new Twitter CEO have raised questions about possible violations of securities or other laws.

“Despite widespread concerns about Mr. Musk’s acquisition of Twitter while serving as CEO of Tesla, it remains unclear whether the Tesla board – which has key decision-making authority within the company – is adequately governing the company or if it has established clear rules and policies to address the risks to Tesla posed by Mr. Musk’s dual roles,” the letter read.

Warren’s letter also raised concerns about whether there is a conflict of interest between his roles at Tesla and Twitter, particularly because Tesla competitors like Audi AG advertise on Twitter’s platform, Bloomberg reported.

Recently, Musk has also pulled Tesla engineers to help out at Twitter since he bought the microblogging outlet for $44 billion earlier this year.

Musk later tweeted that the United States (US) has definitely been harmed by having Warren as a senator. Earlier, The New York Times reported on Warren’s letter to the Tesla board.

Meanwhile, the billionaire has also sold Tesla shares worth $40 billion over the past year, as per Reuters reports. 

Shares of Tesla, the world’s most valuable carmaker, is one of the worst performing stocks among major automakers and tech companies this year, as investors worry that Musk’s purchase of Twitter could divert his time away from Tesla.

(With Bloomberg inputs)