Japan-based SoftBank is weighing up whether to launch a formal takeover approach for US cable company Charter Communications, with financing to the tune of $65 billion in place.

Bloomberg, citing people familiar with the matter, reported SoftBank’s chairman Masayoshi Son (pictured) lined up the financing arrangement with four banks as part of his plans to merge the company’s US operator Sprint with Charter.

The development comes just days after Charter said in a statement it was not interested in acquiring Sprint, following reports the US operator had proposed such a merger.

However, according to the latest development, it was in fact Son’s plan all along for SoftBank to acquire Charter, not the other way around, and combine it with Sprint to create a new publicly traded company.

When rejecting the initial proposal, Charter’s board was reportedly aware of the financing, and Son is now considering whether to proceed with a formal offer with a few tweaks.

Son may also first opt to acquire the rest of Sprint, of which SoftBank owns 84 per cent, and then look to buy Charter for cash and stock.

The sources noted a formal offer for Charter is unlikely to come this week, and the SoftBank chief could ultimately decide not to proceed with a bid.

Notably, it could also prove tough for Son to convince cable tycoon John Malone to agree to a deal. Malone’s Liberty Broadband Corporation owns 21 per cent of Charter, and reportedly agreed with the decision to reject Sprint’s initial advances.

Sprint first entered into exclusive talks with Charter, as well as rival cable company Comcast, about a potential partnership in the mobile sector in June.

The discussions also put the brakes on Sprint’s merger talks with fellow US operator T-Mobile US, with a tie-up between the two mooted for some time.

Sprint’s negotiations with the cable companies concluded without a deal in place.

Charter also agreed a separate year-long agreement with Comcast in May, which requires the companies to work together on any negotiations with a mobile operator.

This could also throw a spanner into the works concerning a potential Sprint, Charter tie-up.