Elon Musk on Thursday said he has lined up commitments worth $46.5 billion to finance a Twitter takeover deal, one week after he first made a public offer to buy the social media company.

Musk said he has commitment letters to finance the deal, including two debt commitment letters from Morgan Stanley and other unnamed financial institutions and one equity commitment letter from himself, according to a filing with the Securities and Exchange Commission on Thursday.

Musk said in the filing that he has yet to receive any formal response from Twitter's board to his offer to acquire all of its shares that he does not currently own for $54.20 a piece, a deal that would value the company at around $41 billion. He said he is “seeking to negotiate” a definite acquisition agreement and “is prepared to begin such negotiations immediately” — an apparent reversal from his statement in his acquisition offer letter that it would be his “best and final" offer.

Questions about whether Musk would actually be able to finance his acquisition of Twitter swirled in the days following his takeover bid, especially after he said in an interview the day of his offer that, "I'm not sure I'll actually be able to acquire [Twitter].”

Although he is the richest person in the world, much of Musk's wealth is tied up in Tesla stock, and some followers of the company speculated that it could be challenging for Musk to raise debt against the historically volatile stock.

While Twitter's board has not formally responded to Musk's offer, it implemented a so-called poison pill on Friday, a defensive measure that could make it harder for him (or any other investor) to buy or take a controlling stake in the company without its approval. (CNN)