Elon Musk and the board of Tesla should be investigated by regulators over possible “conflicts of interest” following the billionaire’s takeover of Twitter, a former US presidential candidate has urged.

Left-wing senator Elizabeth Warren sent a letter to the US Securities and Exchange Commission (SEC) asking it to examine potential “misappropriation of corporate assets, and other negative impacts to Tesla shareholders” since Mr Musk acquired the social media platform last year.

In the nine-page document, Ms Warren wrote that the Tesla board’s “apparent lack of independence” from Mr Musk, combined with “inaction and incomplete disclosures, raise questions about possible violations of securities laws and exchange rules which fall under SEC’s jurisdiction”.

A spokesperson for the SEC said chairman Gary Gensler “will respond to Members of Congress directly”.

Mr Musk appointed himself as Twitter chief executive after completing the $44bn deal and has since cut more than three-quarters of staff. 

He has also authorised teams of workers from Tesla and SpaceX to assist him there.

Last month, Mr Musk appointed former NBCUniversal executive Linda Yaccarino as the new chief executive of Twitter. 

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