Elon Musk fired Twitter's entire board of directors Monday, just a week after finalizing the $44 billion takeover of the social media giant.

The swift move made the Tesla and SpaceX CEO the sole director of Twitter.

"This is just temporary," tweeted Musk after purging the company's top leadership.

Among those fired were Chief Executive Parag Agrawal, Chief Financial Officer Ned Segal and former chairman Bret Taylor.

Musk, the world's richest person, has also offered to buy back all of Twitter’s outstanding bonds, according to a U.S. Securities and Exchange Commission (SEC) filing.

In a separate SEC filing, Saudi Prince Alwaleed bin Talal had become Twitter’s second-largest shareholder to the concern of US Senator Chris Murphy from the state of Connecticut.

"Today I am requesting the Committee on Foreign Investment — which reviews acquisitions of U.S. businesses by foreign buyers — to conduct an investigation into the national security implications of Saudi Arabia's purchase of Twitter," tweeted Murphy.

"We should be concerned that the Saudis, who have a clear interest in repressing political speech and impacting U.S. politics, are now the second-largest owner of a major social media platform," Murphy continued. "There is a clear national security issue at stake and CFIUS should do a review."

Musk's takeover of Twitter has ignited a firestorm of debate regarding free speech versus online harm, with Musk himself previously criticizing Twitter’s moderation policies and accusing the platform of being biased towards left-wing views.

Musk has not yet detailed the exact plans for his vision of Twitter, but he is widely expected to ease moderation rules as well as slash the company's staff.

He is also believed to be entertaining the idea of asking users to pay for the "blue check" mark which is used to verify prominent accounts of celebrities, politicians, business leaders and journalists.