New York - Tesla's owner Elon Musk offered to buy Twitter for $54.20 a share just weeks after he became the social media company’s largest shareholder.

Musk said this was a “best and final offer,” representing a 54 percent premium over the share price the day before he began investing in the company in late January, according to a Securities and Exchange Commission filing.

Mr. Musk, who has nearly 82 million followers on Twitter, has been quiet in recent days. He posted a link to the filing shortly after it was made public: “I made an offer.”

His offer would value the company at about $43 billion.