Elon Musk has secured US$46.5 billion in funding to buy Twitter Inc. and is considering a tender offer for its shares, a filing with US regulators showed on Thursday. Musk himself has committed to put up $33.5 billion, which will include $21 billion of equity and $12.5 billion of margin loans, to finance the transaction. Banks, including Morgan Stanley, have agreed to provide another $13 billion in debt secured against Twitter itself, according to the filing. Twitter was not immediately available for comment. Musk’s latest move comes after Twitter failed to respond to his offer and adopted of a “poison…